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Products => Test Equipment => Topic started by: Amysmith on July 28, 2017, 05:16:02 am

Title: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Amysmith on July 28, 2017, 05:16:02 am
I looking very cheap FY6600 arbitrary waveform signal generator on ebay, the sine wave support 30Mhz, 50MHz, 60MHz on different models, and  arbitrary waveform to 10MHz.
with voltage control output function.

http://www.ebay.com/itm/FeelTech-FY6600-2-CH-DDS-Function-Arbitrary-Waveform-Pulse-Signal-Generator-VCO-/263105160109? (http://www.ebay.com/itm/FeelTech-FY6600-2-CH-DDS-Function-Arbitrary-Waveform-Pulse-Signal-Generator-VCO-/263105160109?)

Only 90.79 USD for 30HMz, so I'm thinking buying one.
Does anybody on this forum have experience with the FeelTech FY6600 function generator?

(http://i.ebayimg.com/images/g/MUkAAOSwPbBZdrS3/s-l1600.png)

Who has bought this FY6600?
How accurate and reliable is it?

I will grateful for any suggestion from all. :-+ :-+ :-+
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: nctnico on July 28, 2017, 08:37:20 am
I guess this is a beefed up version of the older models. The price is pretty sweet though for a 60MHz function generator! I'm wondering what the TTL outputs can be used for. Digital pattern generation would be nice.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on August 05, 2017, 01:42:36 am
Interesting unit. I see that, apart from the upper limit of the sine wave output, there appears to be no functional difference between the 30MHz unit and the 60MHz one (25MHz square wave and 10MHz for all others). Has AM/FM/ASK/PSK/FSK/VCO and AWG capability. Would be nice to see a comparison of this with the JDS unit.

My old analog Wavetek does AWG... you just have to hit it hard enough. Time for a new unit, I think.  ::)

PS: Here is the FY6600 Manual, in case anyone is interested: http://kenswu.zzvps.com/Function/Manual/FY6600%20Series%20Users%20Manual%20V2.2.pdf (http://kenswu.zzvps.com/Function/Manual/FY6600%20Series%20Users%20Manual%20V2.2.pdf)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Mr. Scram on August 05, 2017, 07:22:58 pm
Has anyone checked what voltage(s) the internal power supply provides to the rest of the system? I am fairly interested in this model, but I have issues with using Chinese budget power supplies on mains. I am just not comfortable with that. Maybe that upgrading the power supply to something trustworthy could soothe my worries.

If there is no easy way to upgrade the power supply, I might order the competing JDS6600 instead. That uses a 5V plug-pack that is easily swapped for a trustworthy supply.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: MadTux on August 05, 2017, 08:01:53 pm
There is already a teardown available on youtube:
https://youtu.be/LNBX3yrp5ps?t=1m43s (https://youtu.be/LNBX3yrp5ps?t=1m43s)
Test from the same guy:
https://www.youtube.com/watch?v=hKgg8y5K0ls (https://www.youtube.com/watch?v=hKgg8y5K0ls)

IMO just the classic chinese plastic box with a minimal amount of electronics inside.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Mr. Scram on August 05, 2017, 10:10:45 pm
Has anyone checked what voltage(s) the internal power supply provides to the rest of the system? I am fairly interested in this model, but I have issues with using Chinese budget power supplies on mains. I am just not comfortable with that. Maybe that upgrading the power supply to something trustworthy could soothe my worries.
I just noticed the mechanical switch on the back. The option to switch the unit off properly changes the proposition a little bit, as you can actually turn the supply completely off when you are not around. However, I would still rather see a plug-pack powered device.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on August 06, 2017, 12:06:51 am
Has anyone checked what voltage(s) the internal power supply provides to the rest of the system? I am fairly interested in this model, but I have issues with using Chinese budget power supplies on mains. I am just not comfortable with that. Maybe that upgrading the power supply to something trustworthy could soothe my worries.

If there is no easy way to upgrade the power supply, I might order the competing JDS6600 instead. That uses a 5V plug-pack that is easily swapped for a trustworthy supply.
Going by the teardown video, the PSU looks reasonable and fairly straightforward if you want to replace with your own. Its on its own separate board with lots of extra internal space. Looks like two, maybe three, different output voltages.

EDIT: Looking at the video its 6 lines, 2 X 5V, 2 X GND, 2 X 12V.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Mr. Scram on August 06, 2017, 01:59:16 am
EDIT: Looking at the video its 6 lines, 2 X 5V, 2 X GND, 2 X 12V.
Good eye. I looked for markings on the main board, but missed the voltages on the power board.

Those are very convenient voltages. There are plenty of power supplies available with those, including ATX and other PC power supplies. The trick is to find one that fits neatly into that box.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on August 06, 2017, 03:30:04 am
EDIT: Looking at the video its 6 lines, 2 X 5V, 2 X GND, 2 X 12V.
Good eye. I looked for markings on the main board, but missed the voltages on the power board.

Those are very convenient voltages. There are plenty of power supplies available with those, including ATX and other PC power supplies. The trick is to find one that fits neatly into that box.
Its only my speculation from what I could see on the video. I'll probably order one sooner rather than later and can post up a review... when it arrives.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: StillTrying on August 06, 2017, 11:44:32 am
Is it just me that thinks  00'010.000'000'000KHz  is a horrible way to show 10kHz. Does it need to be shown to 1 millionth of a Hz ?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Specmaster on August 06, 2017, 01:03:57 pm
If you hang a while, there will more then likely be another similar unit launched by another company in China (Minghe) that will do away the SMPS and its associated possibility of high voltages on the ground of the BNC and USB sockets by using a 5VDC wall wart to feed the unit.  Its smaller less powerful cousin 20Mhz or 25Mhz has been tested and people have noticed tingles when using them. I have a Minghe MHS-5200A that uses the 5vdc wall wart, no problems with that at all.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Specmaster on August 06, 2017, 01:16:14 pm
It seems that there is another unit already on Ebay that goes upto 40Mhz but with a wall wart, here's the link http://www.ebay.co.uk/itm/24-25-30-40MHz-Dual-channel-DDS-Arbitrary-Waveform-Function-Signal-Generator-Kit/172775654978?_trksid=p2481888.c100651.m4497&_trkparms=aid%3D777001%26algo%3DDISCO.FEED%26ao%3D1%26asc%3D20160801204525%26meid%3D87253c69a4d8403598de045c372b2e6f%26pid%3D100651%26rk%3D1%26rkt%3D1%26&_trkparms=pageci%253Aa06cd29b-7aa8-11e7-afd3-74dbd180fb11%257Cparentrq%253Ab7ab21da15d0aa48d8bc3de8fffcbe6c%257Ciid%253A2 (http://www.ebay.co.uk/itm/24-25-30-40MHz-Dual-channel-DDS-Arbitrary-Waveform-Function-Signal-Generator-Kit/172775654978?_trksid=p2481888.c100651.m4497&_trkparms=aid%3D777001%26algo%3DDISCO.FEED%26ao%3D1%26asc%3D20160801204525%26meid%3D87253c69a4d8403598de045c372b2e6f%26pid%3D100651%26rk%3D1%26rkt%3D1%26&_trkparms=pageci%253Aa06cd29b-7aa8-11e7-afd3-74dbd180fb11%257Cparentrq%253Ab7ab21da15d0aa48d8bc3de8fffcbe6c%257Ciid%253A2)

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on August 06, 2017, 02:33:22 pm
If you hang a while, there will more then likely be another similar unit launched by another company in China (Minghe) that will do away the SMPS and its associated possibility of high voltages on the ground of the BNC and USB sockets by using a 5VDC wall wart to feed the unit.  Its smaller less powerful cousin 20Mhz or 25Mhz has been tested and people have noticed tingles when using them. I have a Minghe MHS-5200A that uses the 5vdc wall wart, no problems with that at all.

That's the JDS6600 which has the wall wart, already a thread or two on it in the forum. It appears to be 12 bit rather than 14 and have no modulation capabilities. The internal PSU on the FY6600 seems to have changed a little from the ones used in the FY3224S with at least the inclusion of an X-class cap. But its probably the crappy xformer leaking the AC onto the ground. I like the physical buttons on the JDS.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: nctnico on August 06, 2017, 04:01:02 pm
If you hang a while, there will more then likely be another similar unit launched by another company in China (Minghe) that will do away the SMPS and its associated possibility of high voltages on the ground of the BNC and USB sockets by using a 5VDC wall wart to feed the unit.  Its smaller less powerful cousin 20Mhz or 25Mhz has been tested and people have noticed tingles when using them. I have a Minghe MHS-5200A that uses the 5vdc wall wart, no problems with that at all.
Most wall-warts have capacitors connected to mains which results in half the mains voltage at the output so that isn't a solution. The best is to fit a ground outlet in the function generator.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Specmaster on August 06, 2017, 06:07:43 pm
you also of course have the option of powering it from a battery pack if required.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Mr. Scram on August 06, 2017, 09:15:59 pm
Most wall-warts have capacitors connected to mains which results in half the mains voltage at the output so that isn't a solution. The best is to fit a ground outlet in the function generator.
This is where my lack of experience shows. You say a wall wart is not an adequate solution?

What would be needed to hook it up correctly and how would one go about it? Replacing the two prong socket and switch with a three prong fused socket should be doable. I know ground often is hooked up to the case or chassis of the device, but this case is plastic. How would you then hook the ground up internally? Is it as simple as connecting internal ground to the ground pin, so that the fuse box in your house can detect any difference between incoming and outgoing power?


That's the JDS6600 which has the wall wart, already a thread or two on it in the forum. It appears to be 12 bit rather than 14 and have no modulation capabilities. The internal PSU on the FY6600 seems to have changed a little from the ones used in the FY3224S with at least the inclusion of an X-class cap. But its probably the crappy xformer leaking the AC onto the ground. I like the physical buttons on the JDS.
Modulation is also what interests me about the Feeltech. I currently have no use for it, but if history is any indication, I will as soon as I purchase the device without it :D
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Specmaster on August 07, 2017, 12:01:58 am
Like Nitco said most cheap and certainly the supplied wall wart with the unit I suspect will have the capacitor but you can get better ones that are multi-voltage out ones that normally have a linear power supply, they will be larger and heavier and considerably more expensive but should well worth it for the piece of mind alone.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Mr. Scram on August 07, 2017, 12:16:27 am
Like Nitco said most cheap and certainly the supplied wall wart with the unit I suspect will have the capacitor but you can get better ones that are multi-voltage out ones that normally have a linear power supply, they will be larger and heavier and considerably more expensive but should well worth it for the piece of mind alone.
I thought he didn't consider it to be a solution because a wall wart leaves the device floating. Guess I was wrong :)



Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cdev on August 07, 2017, 03:39:14 am
Although everybody is alluding to it, for the benefit of newer visitors, let me just recap why everybody is talking about the power supply. If you are just reading about them for the first time, the crucial unvarnished fact is that unmodified, the "ground" connection on the BNCs on the older FY32xx carry leakage voltages high enough not only to damage delicate components many times over, but also to present a shock hazard if somebody is sweaty or has wet hands, under some conditions.

But the big danger it presents is to chips, if its used ungrounded, which is fairly likely given its target market, electronics hobbyists.

So one has to be careful to always ground it - and perhaps even unplug it when it isn't in use.

How much more would it have cost them to do that right?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on August 07, 2017, 03:51:46 am
Someone should mention that unmodified, the "ground" connection on the BNCs on he older FY32xx carry leakage voltages high enough to damage delicate components many times over, but at low current.

So one has to be careful to always ground it - by means of the shield of the BNCs on the back or similar, when its in use, and unplug it when it isn't.

How much more would it have cost them to do that right?

To be fair its a tough call. Sometimes you want a floating source. Linear supplies are more expensive and heavier (important when shipping from PRC). Something has to give at these prices.

The USB port could always be connected to a grounded source like a PC. The other thing you could do is add another Y class cap from the secondary negative to an external ground source and redirect the primary Y to this ground as well. Internal ground still floats and is isolated but AC has a path to PE.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Kleinstein on August 07, 2017, 05:15:45 pm
The leakage current problem is not so much about an internal or external (wall wart) power supply. It is more about switched mode power supply not using PE or a classical transformer. To meet EMI regulations a SMPS essentially needs the class y capacitor from the output to an RF ground. With a class II supply (using only 2 wires) there are usually 2 Y capacitors towards both sides of the supply and thus half the mains voltage when measured with a high impedance meter. This applies to the cheap internal supply and most SMPS based wall warts. Most instruments should survive the small voltage spikes of the 5 nF (or so) Y cap.

A way around this would be using a supply with a classical transformer or a SMPS with a third wire (PE). The PE connection could be used for a direct connection the GND (e.g. BNC) or just for the y capacitor. So ideally they would have 2 class Y caps from the power pin to warts a PE connection and then a 3rd y cap (and maybe a resistor in the M Ohms range) to the output.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on August 07, 2017, 05:50:04 pm
The leakage current problem is not so much about an internal or external (wall wart) power supply. It is more about switched mode power supply not using PE or a classical transformer. To meet EMI regulations a SMPS essentially needs the class y capacitor from the output to an RF ground. With a class II supply (using only 2 wires) there are usually 2 Y capacitors towards both sides of the supply and thus half the mains voltage when measured with a high impedance meter. This applies to the cheap internal supply and most SMPS based wall warts. Most instruments should survive the small voltage spikes of the 5 nF (or so) Y cap.

A way around this would be using a supply with a classical transformer or a SMPS with a third wire (PE). The PE connection could be used for a direct connection the GND (e.g. BNC) or just for the y capacitor. So ideally they would have 2 class Y caps from the power pin to warts a PE connection and then a 3rd y cap (and maybe a resistor in the M Ohms range) to the output.

Yes. This was my thought. A simple "fix" would be to change the power connector to an IEC and then add a Y cap (and maybe a high value resistor) from internal ground to PE. That should droip the leakage to very low levels. And if you don't need a floating output, just short the internal ground to PE.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Mr. Scram on August 07, 2017, 06:07:32 pm
A way around this would be using a supply with a classical transformer or a SMPS with a third wire (PE). The PE connection could be used for a direct connection the GND (e.g. BNC) or just for the y capacitor. So ideally they would have 2 class Y caps from the power pin to warts a PE connection and then a 3rd y cap (and maybe a resistor in the M Ohms range) to the output.
I found this power supply. Even though it is obviously switching and cheap, it does have a third prong and does come from a reputable source. I was suprised the shipping does not kill it either.

https://www.sparkfun.com/products/11296 (https://www.sparkfun.com/products/11296)

So this is the one to get, aside from the ground concern? What is different about the 60M version?[/]

I might hack the case to install a 3-prong receptacle and set up a grounding circuit inside the unit since there is so much room.

Is there an English language review? Dave?
I am curious about the differences between the versions too and whether they are actually different, or just firmware limited.

Dave seems to be quite harsh on anything cheap and Chinese, so I do not expect a recommendation from him.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on August 07, 2017, 06:14:42 pm
A way around this would be using a supply with a classical transformer or a SMPS with a third wire (PE). The PE connection could be used for a direct connection the GND (e.g. BNC) or just for the y capacitor. So ideally they would have 2 class Y caps from the power pin to warts a PE connection and then a 3rd y cap (and maybe a resistor in the M Ohms range) to the output.
I found this power supply. Even though it is obviously switching and cheap, it does have a third prong and does come from a reputable source. I was suprised the shipping does not kill it either.

https://www.sparkfun.com/products/11296 (https://www.sparkfun.com/products/11296)

So this is the one to get, aside from the ground concern? What is different about the 60M version?[/]

I might hack the case to install a 3-prong receptacle and set up a grounding circuit inside the unit since there is so much room.

Is there an English language review? Dave?
I am curious about the differences between the versions too and whether they are actually different, or just firmware limited.

Dave seems to be quite harsh on anything cheap and Chinese, so I do not expect a recommendation from him.

One of the 12V lines might be negative like on the FY3200 series. Best get someone to confirm before ordering parts. Yeah, I don't expect any review from Dave. He concentrates on either the professional stuff or the "serious" home lab and I expect he would recommend a used unit of known quality before this one. Problem is that even the cheapest AWG's from brand names go for twice the price or more used and much more if you want more than 25MHz. I am looking to use the unit in a space limited setup as well and this is one of the smaller ones.

As for the differences, in the manual I can only see  the sine wave output as being different between the models. Everything else looks the same. Probably a firmware hack but then its only about $30 difference between the 15MHz and the 60MHz so hardly worth the time.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on August 07, 2017, 07:58:33 pm
I was wondering if you traded resolution for frequency or some other function. I did look at some of the used name brand and did notice how quick it gets expensive.
Same resolution of 1uHz across the board. The only other limitation is the 15MHz unit is restricted to a 15Mhz square as well as sine wave. I think the 30 or 50MHz units are the best value.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Specmaster on August 07, 2017, 08:52:15 pm
I was wondering if you traded resolution for frequency or some other function. I did look at some of the used name brand and did notice how quick it gets expensive.
To some extent this might be true, I have the MHS 5200A version which is 25Mhz and if you look on here and you tube there are plenty of reports and reviews basically slagging it off as it having poor square waves at 25Mhz they say it looked more like sine waves, also stating that it claimed to be capable of 20Vpp but couldn't deliver etc. But in reality, checking the manual reveals the following:-
Sine wave is the only one to go the 25Mhz, all others, Sq, Saw Tooth and Arbitrary waves are up to 6Mhz. output is indeed 20Vpp on all waves up to 12Mhz and after it drops down to 15Vpp.

This I suspect is really a function of the limited supply coming from the built in SMPS, maybe replacing this with a linear power supply may lift this.

Is it really worth paying out for the second hand more well known and very expensive branded lab type of equipment for the average user? I would say, only if you really must have / require the extra functions / accuracy etc that these will provide, maybe if your using them in a business yes but if you're like me, just dabbling at home for the fun of it, then no.

You pay your money and takes your choice, at the end of the day, thats a decision only you can make, but personally, I'd check the manual and see if it can do what you need it to do and take it from there.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: nctnico on August 07, 2017, 09:03:02 pm
I was wondering if you traded resolution for frequency or some other function. I did look at some of the used name brand and did notice how quick it gets expensive.
To some extent this might be true, I have the MHS 5200A version which is 25Mhz and if you look on here and you tube there are plenty of reports and reviews basically slagging it off as it having poor square waves at 25Mhz they say it looked more like sine waves, also stating that it claimed to be capable of 20Vpp but couldn't deliver etc. But in reality, checking the manual reveals the following:-
Sine wave is the only one to go the 25Mhz, all others, Sq, Saw Tooth and Arbitrary waves are up to 6Mhz. output is indeed 20Vpp on all waves up to 12Mhz and after it drops down to 15Vpp.

This I suspect is really a function of the limited supply coming from the built in SMPS, maybe replacing this with a linear power supply may lift this.
No, what is limiting the the maximum output voltage is the slew rate of the amplifier stage driving the output. 20Vpp @12MHz is quite a lot already.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: bitseeker on August 08, 2017, 02:50:07 am
I suppose if you occasionally needed a well-formed square wave, you could have the AWG drive an external Schmidt trigger.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on August 08, 2017, 04:35:17 am
One of the limitations to this unit, suffered by many others I am sure, is that it supports a 20Vpp output only to 10MHz, then 10Vpp to 20MHz and then 5Vpp thereafter. As noted before, this is likely a limitation of the output amplifier. I would suggest buyers RTFM before purchase to know exactly the limitations here.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Mr. Scram on August 08, 2017, 09:46:06 pm
One of the limitations to this unit, suffered by many others I am sure, is that it supports a 20Vpp output only to 10MHz, then 10Vpp to 20MHz and then 5Vpp thereafter. As noted before, this is likely a limitation of the output amplifier. I would suggest buyers RTFM before purchase to know exactly the limitations here.
That's common amongst these cheap units, but if it is properly and accurately specified, there is no problem.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: pi^2 on August 27, 2017, 05:37:07 pm
My FY6600 BNC-ground to Earth-ground Voltage is 94 Volt.
Zing zing zing, not happy about it.
Will have a look for a cheap 30VA isolation transformer.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Mr. Scram on August 27, 2017, 05:45:23 pm
My FY6600 BNC-ground to Earth-ground Voltage is 94 Volt.
Zing zing zing, not happy about it.
Will have a look for a cheap 30VA isolation transformer.
That's what I was afraid of. I'm kind of glad I didn't pull the trigger on this one. With all the extra fiddling and hours measuring and fixing things involved, buying a 'real' unit isn't that much more expensive.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on August 27, 2017, 06:09:48 pm
Wouldn't have cost them more than a few cents to provide a PE supply.  |O
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: nctnico on August 27, 2017, 06:20:08 pm
My FY6600 BNC-ground to Earth-ground Voltage is 94 Volt.
Zing zing zing, not happy about it.
Will have a look for a cheap 30VA isolation transformer.
That's what I was afraid of. I'm kind of glad I didn't pull the trigger on this one. With all the extra fiddling and hours measuring and fixing things involved, buying a 'real' unit isn't that much more expensive.
I don't know what your hourly rate is but putting a IEC socket with earth in and connecting the earth to the 0V of the power supply takes about half an hour. I know many people like to turn this into a big project but that is not necessary at all.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Mr. Scram on August 27, 2017, 06:38:00 pm
I don't know what your hourly rate is but putting a IEC socket with earth in and connecting the earth to the 0V of the power supply takes about half an hour. I know many people like to turn this into a big project but that is not necessary at all.
Just talking about it here has cost me more than half an hour, so that ship has sailed :D Doing research on the construction and parts that have to be ordered, the costs of the parts, putting the parts in and testing whether the problem has been adequately solved all add up. That's probably more than an evening of work. I tend to share your optimistic judgement of project times, and it somehow never seems to pan out.

Of course, it could be a nice project, but I have reached the point where I want to focus more on my actual projects, rather than every tool added becoming a project on its own just to save a few bucks.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: nctnico on August 27, 2017, 06:57:21 pm
I don't know what your hourly rate is but putting a IEC socket with earth in and connecting the earth to the 0V of the power supply takes about half an hour. I know many people like to turn this into a big project but that is not necessary at all.
That's probably more than an evening of work. I tend to share your optimistic judgement of project times, and it somehow never seems to pan out.
Well I already upgraded a FY3000S series so I know it is half an hour of work. And what is difficult about ordering an IEC inlet and a piece of wire (if you don't have these already)?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on August 27, 2017, 07:05:13 pm
I don't know what your hourly rate is but putting a IEC socket with earth in and connecting the earth to the 0V of the power supply takes about half an hour. I know many people like to turn this into a big project but that is not necessary at all.
That's probably more than an evening of work. I tend to share your optimistic judgement of project times, and it somehow never seems to pan out.
Well I already upgraded a FY3000S series so I know it is half an hour of work. And what is difficult about ordering an IEC inlet and a piece of wire (if you don't have these already)?

Did you use a Y cap or just a direct connection?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: nctnico on August 27, 2017, 07:10:17 pm
I don't know what your hourly rate is but putting a IEC socket with earth in and connecting the earth to the 0V of the power supply takes about half an hour. I know many people like to turn this into a big project but that is not necessary at all.
That's probably more than an evening of work. I tend to share your optimistic judgement of project times, and it somehow never seems to pan out.
Well I already upgraded a FY3000S series so I know it is half an hour of work. And what is difficult about ordering an IEC inlet and a piece of wire (if you don't have these already)?
Did you use a Y cap or just a direct connection?
Direct connection. The Y cap is already in the power supply. The problem is the leakage current caused by the mains filter.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on September 03, 2017, 04:01:38 am
English review up on youtube now. Highlights a few hidden bugs.

https://www.youtube.com/watch?v=409mkMmJ-jE (https://www.youtube.com/watch?v=409mkMmJ-jE)

A little disappointed  that he doesn't give any overview of the VCO functions.

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: sp2iqw on September 06, 2017, 10:37:51 am
Few days I have ordered 30MHz version so now I'm waiting  :)

This genarator has very good price/performance ratio so it is hard to expect more in this price range.

Anyone know what is a freqency of an oscillator clocking the Cyclone IV FPGA ? No way to read it on a "a teardown" film available on Youtube (https://youtu.be/LNBX3yrp5ps?t=1m43s)
20ppm specification is rather low comparing to sub-1ppm TCXOs available on the market under 1$.  Of course in majority of apllications that's more than enough.

Michal
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: feeltech on September 08, 2017, 12:52:11 am
First of all, in the absence of the introduction of the ground wire of the two-wire plug of the switching power supply system will have such a situation.
In order to suppress common mode interference, the switching power supply in the design, the "safety capacitor" will be between the "LG / NG" (safety capacitor is used for such occasions, even if the capacitor fails, will not lead to electric shock,  so the secondary side of the switching power supply "ground" is equivalent to the midpoint of the AC voltage, so you measured 110V voltage. But this does not mean there will be security risks, after all, the capacitance capacity of only 1000pf.
If you are still worried about its leakage, then the correct way is to measure its DC leakage resistance, the use of insulation tester is the most effective way
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: bitseeker on September 08, 2017, 12:56:02 am
First of all...

Is this the "real" FeelTech?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: feeltech on September 08, 2017, 01:07:09 am
First of all...

Is this the "real" FeelTech?

Yes, we need to listen to all kinds of opinions or suggestions in order to make the product better.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: bitseeker on September 08, 2017, 03:33:49 am
That's great! Welcome to the forum. :-+

Since you're here, if there is a way to update the firmware in the FY3224S, can you post that info in the FY3224S thread (https://www.eevblog.com/forum/testgear/feeltech-fy3224s-24mhz-2-channel-dds-aw-function-signal-generator/)? Many have asked about it. Thanks!
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: nctnico on September 08, 2017, 08:15:35 am
First of all, in the absence of the introduction of the ground wire of the two-wire plug of the switching power supply system will have such a situation.
In order to suppress common mode interference, the switching power supply in the design, the "safety capacitor" will be between the "LG / NG" (safety capacitor is used for such occasions, even if the capacitor fails, will not lead to electric shock,  so the secondary side of the switching power supply "ground" is equivalent to the midpoint of the AC voltage, so you measured 110V voltage. But this does not mean there will be security risks, after all, the capacitance capacity of only 1000pf.
If you are still worried about its leakage, then the correct way is to measure its DC leakage resistance, the use of insulation tester is the most effective way
Test equipment should not have this problem. The leakage current is big enoug to destroy a circuit so it is very bad!
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: feeltech on September 08, 2017, 08:49:53 am
That's great! Welcome to the forum. :-+

Since you're here, if there is a way to update the firmware in the FY3224S, can you post that info in the FY3224S thread (https://www.eevblog.com/forum/testgear/feeltech-fy3224s-24mhz-2-channel-dds-aw-function-signal-generator/)? Many have asked about it. Thanks!
There is no online upgrade function, if there is an error, can only contact the dealer to replace, we repair and upgrade, but FY6600 after the product we will add online upgrade function.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Mr. Scram on September 08, 2017, 09:00:19 am
Test equipment should not have this problem. The leakage current is big enoug to destroy a circuit so it is very bad!
For me, it is the reason not to buy the unit, along with not trusting no Chinese things on mains. If I can use my own plugpack or power supply, I'm game.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: nctnico on September 08, 2017, 09:07:52 am
Test equipment should not have this problem. The leakage current is big enoug to destroy a circuit so it is very bad!
For me, it is the reason not to buy the unit, along with not trusting no-Chinese things on mains. If I can use my own plugpack or power supply, I'm game.
-sigh- Your own plugpack will have the same problem if it is a switching one.  :palm: And it is probably made in China as well.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Mr. Scram on September 08, 2017, 09:47:54 am
-sigh- Your own plugpack will have the same problem if it is a switching one.  :palm: And it is probably made in China as well.
Note it's a two part remark. One is about not blowing your DUT up. That will not be solved by a switching plugpack, though picking the right power supply might. The second part is about not burning your house down, which, if I have to choose, is my biggest priority.

Also note the difference between "Chinese" and "made in China". The first denotes something designed, sold or made by an unknown Chinese company, with no local legal entity to address in case of trouble. The second includes products designed and sold by reputable companies that have much to lose in case of neglect. Buying a decent brand microwave and finding out it's made in China? Fine. Buying an unbranded mains to DC power supply off of eBay and actually using it? No, thank you kindly.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: inqubi on September 08, 2017, 07:45:49 pm
Hi

I have just discovered this forum searching the web for any Feeltech support...

Ordered on eBay, my FY6600 has been delivered today and after checking its CD proved not to be properly burned. Could somebody be so kind and upload somewhere (any cyberlocker You like:  https://mega.nz (https://mega.nz)  https://mediafire.com (https://mediafire.com)  http://catshare.net (http://catshare.net) ....) zipped all its content ??

A link to uploaded CD, posted earlier in this thread is down now.

Many Thanks!
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: feeltech on September 09, 2017, 03:24:06 am
Hi

I have just discovered this forum searching the web for any Feeltech support...

Ordered on eBay, my FY6600 has been delivered today and after checking its CD proved not to be properly burned. Could somebody be so kind and upload somewhere (any cyberlocker You like:  https://mega.nz (https://mega.nz)  https://mediafire.com (https://mediafire.com)  http://catshare.net (http://catshare.net) ....) zipped all its content ??

A link to uploaded CD, posted earlier in this thread is down now.




Many Thanks!
FY6600 User Guidehttps://drive.google.com/file/d/0B3N_NW8vylrmaHFRLXloOVJQYjA/view?usp=sharing (https://drive.google.com/file/d/0B3N_NW8vylrmaHFRLXloOVJQYjA/view?usp=sharing)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: sintechs on September 12, 2017, 12:01:55 pm
but FY6600 after the product we will add online upgrade function.
You mean that FY6600 already has the ability to upgrade firmware online?
I'm asking this because some sellers have FW ver. 2.6, others 2.8.
Does it make sense to buy the latest firmware now, if online upgrade going to be available soon?
Could you please describe the difference between 2.6, 2.8, 2.9?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: feeltech on September 16, 2017, 09:04:14 am
but FY6600 after the product we will add online upgrade function.
You mean that FY6600 already has the ability to upgrade firmware online?
I'm asking this because some sellers have FW ver. 2.6, others 2.8.
Does it make sense to buy the latest firmware now, if online upgrade going to be available soon?
Could you please describe the difference between 2.6, 2.8, 2.9?
Function is not much difference, just fix some of the different languages show the problem
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on October 13, 2017, 06:13:55 pm
Hi

I have just discovered this forum searching the web for any Feeltech support...

Ordered on eBay, my FY6600 has been delivered today and after checking its CD proved not to be properly burned. .../...
A link to uploaded CD, posted earlier in this thread is down now.

Many Thanks!

Hi all,
The same for me, the CD I received with the Feeltech FY6600 (rev 3.1) last week is 100% unreadable (I checked it on 3 PC, all 3 with the same issue)
I really need the software to play arbitrary signals.
Someone can help me by posting the software ? (email or cloud)

Thanks a lot
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on October 28, 2017, 05:51:34 pm
Hi All

also got a FeelTech FY6600
regarding CD: I don't even know if I can read it. I do have an old PC with CD collecting dust somewhere, but I don't feel like digging it out. So if anyone does get a link...


I played around a bit with the FY6600, and it seems to work OK. Sine is exactly the same as generated by the one build into my DS1074Z-S. (I compared with A-B math function) Square has a slightly better rise time (about 8ms instead of the 12ns of the build in.) And control is a *lot* easier. That is the biggest problem with the DS1074Z-S build in: really bad controls. Frequency wise, on a 15Mhz signal, they differ about 100Hz, drifting back and forth a bit. So about 6ppm. I suspect that is pretty OK for cheap equipment like these two.


Signal wise, I found only one problem: all vertical edges (square, step, sawtooth) have a 5ns variance in timing. Regardless of the frequency, you always get runt edges 5ns apart. I suspect the max resolution of some internal CPU or DAC frequency is showing here. It of course is only important for higher frequencies, shown is 15Mhz. The Blue one is the DS1074S-Z internal signal, its fuzzy because I am triggering on the yellow FY6600. As you can see, apart from the 5ns variance, the FY6600 has a better rise time and a better shape.


Control wise, it works a *lot* better then the DS1074Z-S internal signal gen. Pretty intuitive too.

A few minor control annoyances:

- You cannot stop the modulation. You can select other modulation parameters, but you cannot stop. The only way I found is to set it to use Channel 2 as mod source (that is default anyway) and then stop channel 2. That will go back to normal signal gen mode. Unlike Sweep, which you can start, and stop at will. Just press CH1...Doh.

- The "Wave" button does not only highlight the waveform menu option, so the rotary button can be used on that menu, but immediately advances the value selection as well. Iow, selects the next waveform. This is different than all the other buttons (like Freq, Ampl, Offs, Duty, Phas) which all select the menu on the first press, and only the second press advances the value (or you can use the rotary button). Not very important, but a bit annoying.
 
- 00'010.000'000'000KHz is a pretty weird way of writing 10 Khz. I had to stare at that for a while. I think there are better ways to indicate the frequency. 
Edit: And now it is displaying 00'002'000'000'000uHz to show 2KHz. 2 billion microHerz  :palm: Must be a setting somewhere.... OK, not important. The value is technically correct.


So since FeelTech seems to be reading this topic, please take note.

Thanks

Edit: to get these square waves without overshoot, I had to properly terminate with 50 Ohm.
Edit2: This is a FY6600-60M version 3.1 English

(https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/?action=dlattach;attach=364945;image)

More edit: SYNC

I also played with the SYNC function. It has external SYNC in and out, and supposedly you can link multiple devices together, as well as sync CH1 anc CH2.
Some problems with both:

While I do not have two devices, when I put mine in master mode, all it outputs is a 1V square wave that matches CH1 (0V~1V 50 Ohm). No fancy protocol. So you'd think I can also link any other signal source if I match that. No avail, whatever I try, I am not getting it to follow another signal source. Some disclosure by FeelTech would be nice.


SYNC between CH1 and CH2 it works better. It all works nicely at lower frequencies, lets say < 5MHz, but at higher frequencies, the phase starts to go wrong.

The problem seems to be that CH1 and CH2, when "in phase" are still 4ns apart. Again this 4ns (I now believe the 5ns above is also 4ns)
This is of course due to the 250MSa/s specification for the device: 250MSa/s means 1 sample every 4 ns

 That means that if you specify 0 degree phase difference, at <5 MHz frequencies, they are pretty much in sync (4ns = 7 degrees).
But at 60MHz they are pretty much in quadrature (4ns = 86 degrees)
So if you specify 86 degrees offset, they are actually in-phase.

So, at 5Mhz, in-phase is indeed in-phase (roughly). But then if you dial up to 60MHz, you visibly see it shift out of phase.
Now here is the weird thing: You can still then correct the 60MHz to in=phase, by setting it to 86 degrees.
And even weirder, somehow you can also set it to all phases in-between with a pretty good resolution.
I think its because the Sine at this point is filtered rather then sampled, but I was still surprised by it.

It does mean FeelTech could fix this, they could "correct" the phase automatically with software, just like I can manually.
And indeed, the DS1074Z-S internal generator does not have these problems, even though its only using a 200MSa/s DAC.
Use equal length cables dummy!

Yet more edit: SWEEP

It works. But I suddenly realize I miss a sweep/trace/scan output. Not sure what the name is. But a sawtooth that shows how far the sweep is, and that I can feed into my scope as X trigger.

One could naturally have this if CH2 could be used as driver for the sweep in stead of VCO, but that is not an option: only fixed time window and VCO are allowable sources.
So I took CH2, looped it into the VCO and that works but it is a bit unclean. In fact, I found it better to simply put a sawtooth on CH2 and do FM modulation, that also causes a frequency sweep. AM for amplitude sweep. For PWM, still have to use the CH2-VCO loop.

Request/suggestion to Feeltech: allow CH2 as source for Sweep, using the default 5Vpp as normal rather then the 0-5V from VCO. Or alternatively, output the set sweep time values as sawtooth on CH2.


Still good. I wanted a device that is easier to control then the DS1074Z-S internal one, and that can do SWEEP.
I don't think I will be often running at high frequencies. And the sweep is 'workable'. So I am happy with the device. For now.

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on October 29, 2017, 08:18:45 pm
Hi there,

I ordered one for its capabilities with arbitrary signals and modulation too.
I played around with it (FY6600-30M version 3.1 English)  for days now, its a nice generator full of features and not very expensive.

but I'm facing a weird situation with the sine wave, and only with the sine on both channels. |O

When I select the sine wave from the stored waves (1st position, not arbitrary number 24 which is okay), sine is no more displayed on the FY6600 screen like other waveforms, and the signal on the output is really crapy.
The sine wave seems to be "modulated" with sharp pulses.
It happens only with the sine wave selected, other waveforms are ok.

I made a soft reset, tried to play with all the parameters and found nothing relevant to restore that situation.

I really need some help from you guys ;-)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on October 29, 2017, 09:52:01 pm
Was it always like that, or is that new?
What exactly do you mean by: "sine is no more displayed on the FY6600 screen like other waveforms"

My interpretation of that phrase is: The little graph/icon of the waveform is gone or messed up.
Maybe add a photo? And a snapshot of the actual waveform with peaks?

But if so, I would guess flash/eeprom corruption of the area where waveform 1 is stored.

Did you manage to get the software to work, and did you upload your own arbitrary waveforms?
Because I guess they are all stored waveforms, maybe it is a bug and the  software accidentally overwrite the Sine instead of Arb1
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: gby on October 29, 2017, 11:12:36 pm
A couple of people have been unable to read the CD that came with their generator.  Unfortunately the Feeltech website (http://en.feeltech.net/ (http://en.feeltech.net/)) does not have FY6600 files for download yet.  Since I was able to read my CD I made a zip file of just the files relevant to the FY6600 and put it up on https://wetransfer.com/ (https://wetransfer.com/) on a free hosting.  Since this is a free hosting it will only be available for 7 days so get it right away.

https://we.tl/2UmRtktEZy (https://we.tl/2UmRtktEZy)

I haven't loaded it myself yet but would be interested in folk's experience with it.

Enjoy
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on October 30, 2017, 10:22:22 pm
Was it always like that, or is that new?
What exactly do you mean by: "sine is no more displayed on the FY6600 screen like other waveforms"
New after using 2 times
Quote
My interpretation of that phrase is: The little graph/icon of the waveform is gone or messed up.
Maybe add a photo? And a snapshot of the actual waveform with peaks?
When the sine waveform is selected, the graph on the display is now a flat line  :-[

Quote
But if so, I would guess flash/eeprom corruption of the area where waveform 1 is stored.
Did you manage to get the software to work, and did you upload your own arbitrary waveforms?
Because I guess they are all stored waveforms, maybe it is a bug and the  software accidentally overwrite the Sine instead of Arb1
I agree with you, something went wrong with data stored in the eeprom.
Today I've installed the program on my PC, however there's no way to overwrite the datas stored in the eeprom (only the bank corresponding to the arbitrary waves from 1 to 64 slots can be managed)

Thanks Cybermaus for your help :)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Specmaster on October 30, 2017, 11:33:53 pm
Contact the seller about getting it repaired or replaced under warranty.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: xzswq21 on November 01, 2017, 02:52:09 pm
Hello
I want to buy a function generator
which one has the better quality? JDS600 or FY6600?

Thanks
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 01, 2017, 03:30:33 pm
Hard to say man.

My personal feel is FY has more options, and if you look at the square wave rise time in this link (https://www.eevblog.com/forum/testgear/anybody-know-anything-about-this-signal-generator/msg1240749/#msg1240749) from the JDS thread vs mine above, I'd say FY also as better quality in square signals (they all can do a proper Sine, sine is easy, that's why they always rate their highest frequency on the Sine wave).

But in reality: If you want "quality" above 5MHz you'd probably need to step up your budget.
And if you are looking for play and hobby, they are probably both "good enough"

Thats my 5ct anyway. No-one seems to actually have both devices, so its all subjective.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: xzswq21 on November 01, 2017, 04:15:35 pm
Dear
I want to tune my medical board. I should increase the frequency from 10KHz to 20MHz and check the close loop response (AC Analysis)
another usage is checking the step response of my circuit. actually measuring the amount of overshoot. 100KHz or 1MHz clean pulse waveform is adequate.
all the ports are terminated at 50R. the test signal should be 1Vpp at 50R.
if you have one please show me the quality of square wave from 10KHz to the Maximum frequency. it's very important.

Regards
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 01, 2017, 09:02:06 pm
10KHz 1Vpp terminated at 50 Ohm (so shows as 0.5Vpp):
(https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/?action=dlattach;attach=366374;image)

Same, but completely zoomed into risetime of 7.4ns (see measurement in lower left corner)
A small wiggle, not does not really overshoot at all.
(https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/?action=dlattach;attach=366376;image)

Same, but at 1MHz 10MHz
(https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/?action=dlattach;attach=366378;image)

Same but at 25MHz, the official top frequency for square wave for this device
Note that there are no 5ns runt flanks as described in the post above. That is because 25MHz is a perfect divider of the 250MSa/s DAC. With 24MHz or 26MHZ runt flanks again.
(https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/?action=dlattach;attach=366380;image)

Same, but at 50MHz square pulse. This is above device specification, but you can turn the knob up all the way to this.
It basically became an attenuated sine wave, not really a square anymore:
(https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/?action=dlattach;attach=366383;image)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: xzswq21 on November 01, 2017, 10:33:33 pm
Dear
I really appreciate you for your work :)
I think the quality is good.
actually when you have a 50MHz sine generator the maximum frequency of a good quality Square wave should be 10MHz.
consider you want to design a 50MHz sine signal generator. you should filter the output to have a good SNR and THD.
for example you set the f-3dB of the LPF at 75MHz.
now if you order to generate a 50MHz square signal it will be Sine signal as you have shown in the above pic! :)
it's not a drawback.

another way is converting a sine signal to a square signal using a fast comparator and a high speed buffer.
http://www.arrl.org/files/file/QEX_Next_Issue/May-Jun_2013/Fernandes_QEX_5_13.pdf (http://www.arrl.org/files/file/QEX_Next_Issue/May-Jun_2013/Fernandes_QEX_5_13.pdf)
 :popcorn:
http://www.high-voltage-lab.com/186/self-powered-sine-to-square-wave-converter (http://www.high-voltage-lab.com/186/self-powered-sine-to-square-wave-converter)

you can see a 200MHz high quality signal generator in the below! (it's only 100$)
look at the Spectrum Analyzer's pics.
https://www.circuitsonline.net/forum/view/130301 (https://www.circuitsonline.net/forum/view/130301)
it's another project:
https://wiki.electroniciens.cnrs.fr/index.php/Le_groupe_DDS (https://wiki.electroniciens.cnrs.fr/index.php/Le_groupe_DDS)
AD9954 is another DDS IC. (check aliexpress or ebay)

if you have free time would you please do a test?
set your function generator in Sine mode and 2Vpp. (terminate your Oscope at 50R)
change the frequency from 10KHz to the maximum frequency step by step. (for example in 10 steps ... more points is better)
each time turn on the FFT function and set the Average to 64 or 128.
now measure the peak magnitude and write it in a Table.
would you share the Table? :)

Best Regards
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on November 02, 2017, 09:43:06 am
Hi all,

Just a practical tip if you tried to talk with the FY6600 over serial com port.
The parameters are 115200/8/n/1 and not 9600/8/n/1 as described in the documentation.

Enjoy talking with your FY6600 !

In attachment, the response to UMO command (return the model of your generator)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: maddin on November 02, 2017, 07:09:51 pm
Hello together,
i have also ordered a FY6600. Because there seems to be a lot of trouble reading the CD i have load the software from the link gpy posted.
Thanks to gpy for upload the CD.

I have scanned the "FY6600 PC Software V5.2.exe" on virustotal.com ; one result: Suspicious_GEN.F47V1016 :-//
Should i been concerned about this ? What's  your experience with the software ?

Best regards
maddin
 
   
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Specmaster on November 02, 2017, 07:20:57 pm
Lots of antivirus programs will see an unknown .EXE file as a potential threat and flag it as suspicious. I doubt you have anything to worry about, nobody else here has reported any problems apart from the odd difficulty reading the CD.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: bitseeker on November 02, 2017, 07:29:32 pm
Then again, if most owners can't read their CD and, prior to gby uploading, didn't have another means for acquiring the software, there could be something awry that we haven't heard about.

It's likely a false alarm, but not a lot of info either way.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: xzswq21 on November 02, 2017, 08:20:53 pm
I would be grateful if you could do the below test:
if you have free time

set your function generator in Sine mode and 2Vpp. (or 2Vpp RMS) (terminate your Oscope at 50R)
change the frequency from 10KHz to the maximum frequency step by step. (for example in 10 steps ... more points is better)
each time turn on the FFT function and set the Average to 64 or 128.
now measure the peak magnitude and write it in a Table.
would you share the Table? :)



Best Regards
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Specmaster on November 02, 2017, 08:32:28 pm
it would drop I expect by quite a large percentage as you approach the upper limits, I know that the previous round of such devices did.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 02, 2017, 08:34:55 pm
Regarding the "virus" : run it against https://www.virustotal.com/#/home/upload (https://www.virustotal.com/#/home/upload) to see if it is a false positive

Regarding the FFT request: The math and FFT on my DS1000Z series is pretty useless, I feel you want someone with a 2000 or 4000 series to do that.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: xzswq21 on November 02, 2017, 08:37:05 pm
No doubt. I want to judge the quality :) if you have one please do this easy test :)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Yannik on November 02, 2017, 08:40:32 pm
Is it possible to adjust the rise/fall time of square waves with this generator? I really need that capability.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 02, 2017, 08:43:20 pm
Pretty sure that is not possible.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: xzswq21 on November 02, 2017, 08:57:58 pm
it's a very interesting option.
due to the 7ns rise time it's mandatory to use 50R terminated devices :)
consider the device use RG174 or RG316 cable, so the velocity factor is 0.7 now if you want to not encounter some problem, use 18cm Cable not anymore :)
if you could set the rise/fall time to 38nsec and use a 1m Cable you wouldn't have any problems :)

Thanks
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 02, 2017, 09:06:10 pm
Well, I guess you could always upload a arbitrary wave with such a shape that it is effectively a square with 38ns risetime

Maybe one such wave for 1MHZ, one for 10MHz etc. After all, you got a shitload of 64 ARB positions. One for each of your desired risetimes.


What I did find is that if you take a square, and modulate it with PSK with another square of the same frequency, I get a nice 4.4ns risetime square wave!
I think that is really impressive. I was playing with time-domain reflections to measure length the other day. with a <5ns device I should retry that play.

Edit: In fact, all the vertical edge waveforms (pulse, cmos, reverse sawtooth, all of them), *except* the square seems to be 4.4ns. Only the square has 7.8ns.
And indeed, much cleaner to see cable reflections with 4.4ns. Now I know my pieces of BNC-coax are about 1mtr in length  :P
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on November 02, 2017, 10:10:36 pm
Is it possible to adjust the rise/fall time of square waves with this generator? I really need that capability.
Nope
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on November 02, 2017, 10:26:53 pm
For those who are interested in the spectral behaviour above 1 MHz, I've made some tests with my spectrum analyzer.

Have a look at this :

30M Sine purity, better than 44dB
1M Sine 0dBm, 2nd and 3rd orders are below 52dB, not too bad indeed !
Bandwidth greater than 80MHz with a 10MHz multitone signal test, quite impressive

For <100$ , I've to admit that the results are pretty good !
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Mr. Scram on November 02, 2017, 10:29:03 pm
Lots of antivirus programs will see an unknown .EXE file as a potential threat and flag it as suspicious. I doubt you have anything to worry about, nobody else here has reported any problems apart from the odd difficulty reading the CD.
While it's true that some antivirus solutions will flag certain types of code as suspicious, it's also true that many people ignore reported malware on account of it likely being a false positive. If malware is somewhat decently constructed and depending on the purpose, the user won't notice anything being wrong after getting infected.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: xzswq21 on November 02, 2017, 10:56:40 pm
I'm wondered HOW the designer designed the setup?!
for 1MHz the SFDR is 54dBc :| for a cheap generator is good.
But I can not admit it! they have used a 14-Bit 250MSPS DAC, the frequency is only 1MHz! the SFDR should be better than 80dBc :)
above 70MHz they should use back to back topology (by using two Baluns) to have the better Harmonic Distortion suppression.

*which type of capacitors they have used?!
*which OP-AMPs they have used?

I'm familiar with designing such devices :)

I think it's a good AFG to tune the circuits (without checking the THD and ...) and checking the step response.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on November 02, 2017, 11:30:14 pm
Frankly it is a mistery.
Unfortunately it will be difficult to make some reverse engineering as a lot of ICs have no names (information scratched by Feeltech)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 03, 2017, 04:58:16 am
I am still a bit unhappy about those 4ns runt edges though. Not being a signal generator specialist, it seems to me like a unavoidable problem if you have a 250MSa/s DAC, but I am wondering how my DS1074Z-S internal generator is able to work without such edges when it has an even lower DAC of 200MSa/s


Also, I think I see a JTAG port, so while not officially updateable, it should be possible if we have the firmware and correct procedure.



Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: xzswq21 on November 03, 2017, 08:31:02 am
the Baluns are used for the frequency above 5MHz. when you have back-to-back topology the bandwidth is divided by sqrt(2).
it's recommended for the frequency above 70MHz. I think they have used some schematics from some datasheets.
there is no Baluns to support the frequency below 15KHz.

now let me show you an interesting curve about the SFDR and use of a Balun:
(http://s9.picofile.com/file/8310789234/fy6600_2.PNG)

even I suspect the capacitor's type you have used in the design!
now let me show you an interesting curve about THD+N vs frequency and Vrms:

(http://s8.picofile.com/file/8310790918/fy6600_3.PNG)

(http://s9.picofile.com/file/8310790992/fy6600_4.PNG)

Best Regards

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Marco on November 03, 2017, 06:10:07 pm
I'm pretty sure the two chips next to the FPGA are overclocked DAC904s, to the right of the FPGA are a couple of buffer amps and discrete anti-aliasing filters.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Mr. Scram on November 03, 2017, 06:56:52 pm
so the higher freqency models are just moer overclocked?  |O I just happen to be looking at this on ebay last night, local seller for best price I've seen so far. Almost...
You say it like it's a bad thing. Intel sells the same silicon at different clock speeds for different amoutns of money. Dave has done a video about factory overclocking. If you have tested and can guarantee operation, or even binned the chips, there little wrong with the practice.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: xzswq21 on November 03, 2017, 07:23:54 pm
Dear
I couldn't read any part numbers at that video!
DAC904 is belong to Burr-Brown!
even I see two white components near BNC jacks. can you read the part number?

My brother told me to not buy this Function generator yesterday, he told me to buy a Rigol AFG at-least.
I think the best version of this AFG is 30MHZ bcoz DAC904 is a 160MSPS DAC.

it's worthy to note that some pics I uploaded above are the performance of a 12-Bit DAC!
even the Feeltech's designer couldn't keep the performance of 14Bit DAC904!
bad layout, bad capacitor type and ... will ruin the performance. he could have achieved very better performance even with 10 or 12Bits DAC!!!


Thanks
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on November 03, 2017, 10:15:33 pm
Some photos are following.
Your comments are welcome.

The high res images are stored on onedrive here :
https://1drv.ms/f/s!Alr1uExd0Z7lleYbxrcIoIomOrVprA (https://1drv.ms/f/s!Alr1uExd0Z7lleYbxrcIoIomOrVprA)

There is 14 DAC pins connected to the FGPA, photo FY6600-05 !
It seems to be a DAC904, the pinouts are corresponding to the photo.
The DAC904 is a 14b 165Msps converter produced by Burr Brown or TI.

DAC904 => LPFilter => OPA686


Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: ArthurDent on November 04, 2017, 04:14:53 pm
A couple of comments: the power input connector can easily be changed but the back panel is thin fiberglass so care must be taken when enlarging the opening so you don't crack the panel. Also the power supply already has a unused ground pad that can be used by just soldering the ground wire to it. That ground is carried on the 2 middle pins of the power supply interconnect cable so all the BNC shells on the panel are at zero potential. I've (hopefully) attached a photo showing what I did. 

Also the 50 Mhz oscillator in my unit isn't that great although it may meet the specs. If you have a function generator capable of many digits of resolution but the timebase is only accurate to 5 places, that is a waste. There are unused pads marked "S1" on the main board near the oscillator that may be for an external timebase that I'll look into.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: bitseeker on November 04, 2017, 04:18:08 pm
Welcome to the forum, Arthur and thanks for the info. Looking forward to your findings.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: mk_ on November 04, 2017, 04:34:52 pm
Some photos are following.
Your comments are welcome.

The high res images are stored on onedrive here :
https://1drv.ms/f/s!Alr1uExd0Z7lleYbxrcIoIomOrVprA (https://1drv.ms/f/s!Alr1uExd0Z7lleYbxrcIoIomOrVprA)


Thanks for detailed pictures

Well, at least it shows how not to design passive filter-gnd- areas.
In FY6600 -07.jpg there is only one (!) GND-via visible in the LPF1- filter-area (betweeen C36 and C37) so if this stuff will see the hf this filter will do a lot of jiggel but nothing predictable...
me thinks so the same mistake in LPF2.

michael
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: xzswq21 on November 04, 2017, 05:05:30 pm
even I think the LPF should be placed after the Buffer to reduce the noise effectively not before!
the Buffer is actually a difference Amp.
I see two cap trimmers or 2 res pots. the CMRR of such designs is not good!
L10+C4+C27 and L12+C5+C16 are power supply filters to reduce the noise for the buffer.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 04, 2017, 05:33:33 pm
Also the 50 Mhz oscillator in my unit isn't that great although it may meet the specs. If you have a function generator capable of many digits of resolution but the timebase is only accurate to 5 places, that is a waste. There are unused pads marked "S1" on the main board near the oscillator that may be for an external timebase that I'll look into.

Is that a HHttG reference, or are you actually named Arthur Dent?

Anyway, if we could hook this up to an external 10MHz GPS disciplined reference oscillator, that would be marvelous.

Or even better, directly build in one of the cheap uBlox GPS modules. So we do not need to mess with amps and drivers, but could use the FY6600 itself as an adjustable reference frequency. That would be a nice project. Would make it into a pretty good frequency counter too then.


Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Marco on November 04, 2017, 05:58:23 pm
bad layout, bad capacitor type and ... will ruin the performance. he could have achieved very better performance even with 10 or 12Bits DAC!!!

There is a ridiculous lack of competition in even medium speed DACs/ADCs, higher speed is worse, either they are completely integrated without general purpose use (mobile chipsets, cable modems etc) or you pay a ransom. There are only a couple of chips with really low prices, the DAC904 is one of them ... and it's not all that good to begin with regardless how you use it. Which is why some designs just stick with resistor ladders in this day and age still.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: ArthurDent on November 04, 2017, 06:42:25 pm
You asked: "Is that a HHttG reference, or are you actually named Arthur Dent?"

This is a screen shot of the EEVBlog screen when I just registered. I had to save it because of what the answer to the last question was going to be. Certainly not a coincidence and I almost couldn't believe it! My 'real' name is Arthur Phillip Dent.   ;)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 04, 2017, 06:58:18 pm
That is hilarious  :-DD

But it has to be a coincidence. If people making HH references was normal enough for the web-admin to program such a Easter egg, your username would have been gone already.
Anyway, let me go and make up some towel jokes to include in the next couple of posts...

Edit: waaait a minute: It's actually more likely you decided on that user handle after you read the question ???



More seriously: I was assuming that S1 is a JTAG connector, but admittedly for no other reason that I would expect an unpopulated  JTAG on such a board, I did not follow the traces. But I am still thinking if you want to replace the timebase, you'd have to desolder the xtal module.

Edit: Yes, the chip between the S1 and the 50MHz is a Winbond 25Q16BVSIG : 16MBit Serial Flash with Dual SPI
 (https://media.digikey.com/pdf/Data%20Sheets/Winbond%20PDFs/W25Q16BV.pdf)It has at least 6 connections with the S1, so that makes it *very* likely some sort of SPI based programming header, like JTAG

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 04, 2017, 08:07:01 pm
While following the JTAG, I noticed 4 configuration solder islands labeled J10 J11 and J12 J6
Toward the back of the device, 2 on each side.

Not sure what they configure, my 60M board is coded like this:
J10 - closed by thin pcb trace
J11 - open, no pcb trace and no solder drop

J12 - closed by thin pcb trace
J6  - open, no pcb trace and no solder drop

So no solder drops, nor any scratched traces, meaning default PCB hardware.
I guess it would be too easy if this was the 60M 30M 15M frequency selection, but you guys check anyway.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 04, 2017, 09:04:14 pm
By PM request, some sine pics.

Mind you, not sure why you want these, if you think you can "eyeball" sine quality, you would be better off checking the spectrum pics a page back, they are much more relevant. The only thing you can get from these pics is a slight attenuation toward higher frequencies, which may as well be my scope rather then the AWG.

Also, please note the scope measurement at the bottom cannot be trusted on decimals. It is constantly jumping from 19.8 to 20.0 to 20.2, showing it lacks resolution.

20Mhz to 60MHz 1Vpp 50 Ohm
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Diabolo on November 05, 2017, 01:35:48 am
Hello,

https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/?action=dlattach;attach=366988;image (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/?action=dlattach;attach=366988;image)


The integrated circuit on each side of U302 is MCP 4822E Dual 12-Bit Voltage Output DAC.

Regards,
Diabolo
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: xzswq21 on November 05, 2017, 09:20:32 am
By PM request, some sine pics.

Mind you, not sure why you want these, if you think you can "eyeball" sine quality, you would be better off checking the spectrum pics a page back, they are much more relevant. The only thing you can get from these pics is a slight attenuation toward higher frequencies, which may as well be my scope rather then the AWG.

Also, please note the scope measurement at the bottom cannot be trusted on decimals. It is constantly jumping from 19.8 to 20.0 to 20.2, showing it lacks resolution.

20Mhz to 60MHz 1Vpp 50 Ohm

good job :) I see 0.5dB  attenuation at 20MHz and 2dB attenuation at 60MHz.

when the input impedance of your Oscope is 1M || 15pF and use a 50R capline, the VSWR<1.3 for up to 55MHz.  :horse:
but it depends on the quality of BNC T Adapter and other parasitic inductance, it could be 110MHz.  :bullshit:
so it's better to use an Active Adapter.

Thanks
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on November 05, 2017, 10:29:33 am
The puzzle is almost complete, thanks to all the contributors :-+

1   CH340G             /USB to serial
2   HC245               /octal bus transceiver
3   25Q16BVSIG      /Winbond 16MBit Serial Flash with Dual SPI
4   EP4CE6E22C8N  /FGPA Altera Cyclone4
5   DAC904             /14 bits DAC 165Msps =Channel 2
6   DAC904             /14 bits DAC 165Msps =Channel 1
7   MCP4822E         /Dual 12-Bit Voltage Output DAC (level Ch2)
8   MCP4822E         /Dual 12-Bit Voltage Output DAC (level Ch1)
9   OPA686N           /wideband low noise voltage amplifier
10 OPA686N           /wideband low noise voltage amplifier
11 JRC4558D          /Dual op amp
12 ?                       /wideband amplifier
13 ?                       /wideband amplifier
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on November 05, 2017, 11:38:26 am
Hi all
Did someone tried to play around with arbitrary waves with the FY6600 PC Software?
I'm facing issues when I try to open waveforms that were previously saved (file xxxx.FY).
After having opened the file, the waveform is always not corresponding to the saved one, the scale and the plots are totaly messy  |O

Hereafter, a printscreen of a ramp waveform saved and then reloaded !

Update : the method described above wasn't the right one (thanks to cybermaus), you'd better use "text window" and "add waveform" to perform the handling of custom waveform.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Chris56000 on November 05, 2017, 12:01:50 pm
Hi!

At the price they are it'd be within my monthly pocket-money allowance to buy one simply for the purpose of tearing-down and depopulating for the purposes of compiling a full proper instruction & service manual, and the posts in this thread so far, so if the superb clever chaps on here can pinpoint the last two chips U12 & U13 that'll be the inspiration I need to buy one for reverse-engineering purposes!

Is it worth looking in the EL-series to see if there's a pin-out match for the last two chips? Is there a way of removing the small square ali heat-sink from the O/P amplifier chips without risking wrecking the PCB it's made on?

PS!

1) Can anyone tell me how to extract pictures from PDFs and the little icons on toolbar buttons, etc., like they do to write software/product instruction manuals?

2) Has anyone dismantled the front-panel/display assembly of one of these and got the type-no and pixel-size spec. of the TFT colour display module yet?

Chris Williams
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 05, 2017, 01:08:39 pm
Hi all
Did someone tried to play around with arbitrary waves with the FY6600 PC Software?
I'm facing issues when I try to open waveforms that were previously saved (file xxxx.FY).
After having opened the file, the waveform is always not corresponding to the saved one, the scale and the plots are totaly messy  |O

Hereafter, a printscreen of a ramp waveform saved and then reloaded !

Just works for me:
Opened tool. Made a waveform (combined sine, triangle and ramp), saved it.

Closed program, reopened program, loaded the waveform, no problem (attachment 1)

The only slightly odd thing is, if you "Open" a waveform, you get a dialog that has title&button "Save"
But it is actually loading the file, not saving it. (attachment 2)





Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 05, 2017, 05:29:46 pm
1) Can anyone tell me how to extract pictures from PDFs and the little icons on toolbar buttons, etc., like they do to write software/product instruction manuals?
If you have Acrobat, full version, there is usually a menu item to save all images as jpg. I am not familiar with any 3rd party Acrobat tools. Otherwise, you can just view at 100% and take a screen capture - tedious if there are many images...

Or if your budget is lower, GhostScript is the de-factor free-and-open-version. Very technical, but there are some interfaces like muPDF around it.
And many of the other commercial but cheap PDF tools are usually based on Ghostscript, but dumbed down for easy use.

I have not been active with that for a while, so not up to speed which of the cheap ghostscript wrap-arounds is currently best. Last time I used it was Foxit, actually not based on Ghostscript (or hidden very well). But that was years ago.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: xzswq21 on November 05, 2017, 05:42:31 pm
Hi!
1) Can anyone tell me how to extract pictures from PDFs and the little icons on toolbar buttons, etc., like they do to write software/product instruction manuals?

Chris Williams

Dear
I have prepared a simple video for you: (all the tools is free!)
http://s9.picofile.com/file/8311018192/Untitled_2017_11_05_21_01_24.mp4.html (http://s9.picofile.com/file/8311018192/Untitled_2017_11_05_21_01_24.mp4.html)

if you want to extract the icons from any software, you can use Resource hack or any similar software.

Regards
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: xzswq21 on November 05, 2017, 05:54:26 pm
I want to buy a FY6600 Function generator.
in contrast to the Feeltech's AD, the DAC IC is 160MSPS.
now I'm hesitating whether to choose 30MHz or 60MHz versions. Are you satisfied with your 60MHz version? or 30MHz is better?

Best Regards
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 05, 2017, 06:06:38 pm
Inspired by ArthurDents clock remark, I ordered a uBlox NEO-M8N module (arduino ready) for $10.
At the very least I should be able to turn that into a stand-alone 10MHz GPS reference singal, but maybe also add a x5 PLL and make this AWG run of it.
I took the M8N version, because it has flash, so you can configure it once and then hook it in.

If that works, one would have a better then 1ppm (uBlox claims 5ppb) generator as well as frequency counter.
Then all those digits they display (60.000.000.000.000 uHz) actually make sense  ::)

I am thinking a NB3N502 PLL (https://www.onsemi.com/pub/Collateral/NB3N502-D.PDF), because it can do x5 on a 10MHz signal, as well as passes through the original 10MHz buffered. And it is cheap. But if anyone has other suggestions.

Edit: later thinking is a double NB3N502. Because uBlox writes that only 1, 2, 4, 8 MHZ (any division of the internal 48MHz clock) is jitter free, whereas a 10MHz has significant jitter. So 2.5x VCO PLL on 4MHz would clean up an already good base signal. An 2nd x5 would then buffer out the 10MHz as well as provide the 50MHz.

Also, uBlox claims a 5ppm "holdover" precision when the GPS is not locked, so that is pretty much equal to the current 50.0000 VCXO
Probably because they internally use a 48.0000 VCXO themselves.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Marco on November 05, 2017, 06:13:21 pm
now I'm hesitating whether to choose 30MHz or 60MHz versions. Are you satisfied with your 60MHz version? or 30MHz is better?

Just for reference, there's an Ebay seller which ships from Frankfurt ... and he only sells the 60 MHz version. Don't know if that matters to you, but because it's above the custom limit for my country that clinched it for me. I don't want it for MHz signal generation, so that didn't matter to me.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 05, 2017, 06:22:04 pm
Just for reference, there's an Ebay seller which ships from Frankfurt ... and he only sells the 60 MHz version. Don't know if that matters to you, but because it's above the custom limit for my country that clinched it for me. I don't want it for MHz signal generation, so that didn't matter to me.

Yeah, nowadays I just assume and budget for €20 handling + VAT extra when I buy stuff like that. Most off the bigger items are snatched by customs nowadays. Gone are the free days of the 2005~2015 era. However to my surprise, the FY6600 was *not* taxed.

I am sure they did take it out of the queue and must have handled it, because the address label had been tampered with, a new local Dutch one placed on top and it took an unusual (but not impossible) 5 weeks to arrive. (usual is 2 to 4).

But the expected "please pay extra" letter from KPN was not there. I think they could not recognize it from the X-Ray. 
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: xzswq21 on November 05, 2017, 06:35:48 pm
now I'm hesitating whether to choose 30MHz or 60MHz versions. Are you satisfied with your 60MHz version? or 30MHz is better?

Just for reference, there's an Ebay seller which ships from Frankfurt ... and he only sells the 60 MHz version. Don't know if that matters to you, but because it's above the custom limit for my country that clinched it for me. I don't want it for MHz signal generation, so that didn't matter to me.

there are some sellers in aliexpress. the ship cost is $43,  the total price is $150~$170.
some people here uploaded some pics, the quality based on these pics is good but I'm very concerned about it!  :horse:
you know Chinese manufacturers use very low quality components in their designs! (after 6 month all capacitors, inductors, silkscreen,... will be corrupted)
 
My Brother told me, it's better to buy a Rigol to tune your medical board. (only check AC response and step response, the desired frequency is 10KHz to 20MHz)
for Harmonic distortion and noise analysis I will use other instruments.
I'm a student and don't want to pay money a lot.

Thanks
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Marco on November 05, 2017, 06:41:46 pm
I am sure they did take it out of the queue and must have handled it, because the address label had been tampered with, a new local Dutch one placed on top and it took an unusual (but not impossible) 5 weeks to arrive. (usual is 2 to 4).
The one from Frankfurt I ordered Saturday and I got I think Wednesday, so that's another thing to consider.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on November 05, 2017, 08:17:30 pm
I ordered mine (30MHz version) from Fasttech, they sell both 30 and 60MHz.
Paid 88$ (~75€), with no shipping fees or taxes added.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: xzswq21 on November 05, 2017, 08:33:14 pm
I ordered mine (30MHz version) from Fasttech, they sell both 30 and 60MHz.
Paid 88$ (~75€), with no shipping fees or taxes added.

I have never been seen this website! it seems OK :) the price and shipping cost in the website is lower than aliexpress and other similar.
where is the origin of this website?
Thanks
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Diabolo on November 06, 2017, 01:55:44 am
Hello,

For FY6600 generators the maximum frequency is valid for the sinusoidal signal, the other signals capping at 20-25 mhz.
The 2 integrated circuits under the aluminum radiator are 4558.
The crystal quartz reference for the Altera Cyclone FPGA is still 50 mhz in FY 6600 and FY2300H.
The output level of the signals is guaranteed stable only on 5 volts, or below.
Sellers always indicate the characteristics, you need to consult them.
Pay attention to customs fees that can be charged by the customs of each country.
By going through the NL post we escape customs taxes since NL is European, that's why the delivery labels are replaced.

Regards,
Diabolo
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: xzswq21 on November 06, 2017, 05:54:39 am
Hello,

For FY6600 generators the maximum frequency is valid for the sinusoidal signal, the other signals capping at 20-25 mhz.
The 2 integrated circuits under the aluminum radiator are 4558.
The crystal quartz reference for the Altera Cyclone FPGA is still 50 mhz in FY 6600 and FY2300H.

Dear are you sure the IC is 4558?  |O

device has a 1.7 V/?s slew rate
Unity-Gain Bandwidth: 3 MHz Typ
8 nV/?Hz Typ at 1 kHz

The device is a dual general-purpose operational amplifier, with each half electrically similar to the ?A741, except that offset null capability is not provided.
this amplifier ideal for voltage-follower applications. The device is short-circuit protected, and the internal frequency compensation ensures stability without external components.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on November 06, 2017, 08:31:16 pm
Hi xzswq21
Fasttech is located in Hong Kong.

Regards
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: xzswq21 on November 06, 2017, 10:35:15 pm
it's interesting!
*updated
I hope to @Ebel0410 will post the quality of FY6600-30MHz soon :) :popcorn:


for your information:
I want to make a comparison between SDG1010 (Siglent 10MHz), SDG1032x (High quality Siglent 30MHz) and Fy6600!!!  :-DD

inside the SDG1010 (Siglent 10MHz):

(https://www.eevblog.com/forum/reviews/siglent-sdg1010-function-generator-teardown/?action=dlattach;attach=28699;image)
(https://www.eevblog.com/forum/reviews/siglent-sdg1010-function-generator-teardown/?action=dlattach;attach=28723;image)

inside the SDG1032x (High quality Siglent 30MHz):
(https://www.eevblog.com/forum/testgear/siglent-sdg1032x-mini-teardown/?action=dlattach;attach=289348;image)
this is the quality of SDG1032x:
(https://m.media-amazon.com/images/S/aplus-media/vc/90620621-dffb-45d2-a30c-4e98b3453b42._SR970,300_.png)


inside FY6600:
(https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/?action=dlattach;attach=366988;image)

one of drawback of FY6600 is the LPF is placed before OPAMP.
another thing the Low CMRR of Amp stage (due to design)
(http://s8.picofile.com/file/8311124400/FY6600_6.PNG)
and I don't know about the capacitors type inside FY6600 (at page 4 there are some tech information)
the Layout is very important.
and some area should be ground free!
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Mr. Scram on November 07, 2017, 12:22:08 am
I ordered mine (30MHz version) from Fasttech, they sell both 30 and 60MHz.
Paid 88$ (~75€), with no shipping fees or taxes added.
Can you look at the jumpers mentioned before? It would be most interesting to see the difference with the 60 MHz version.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Diabolo on November 07, 2017, 12:26:55 am
Hello,

For FY6600 generators the maximum frequency is valid for the sinusoidal signal, the other signals capping at 20-25 mhz.
The 2 integrated circuits under the aluminum radiator are 4558.
The crystal quartz reference for the Altera Cyclone FPGA is still 50 mhz in FY 6600 and FY2300H.

Dear are you sure the IC is 4558?  |O

device has a 1.7 V/?s slew rate
Unity-Gain Bandwidth: 3 MHz Typ
8 nV/?Hz Typ at 1 kHz

The device is a dual general-purpose operational amplifier, with each half electrically similar to the ?A741, except that offset null capability is not provided.
this amplifier ideal for voltage-follower applications. The device is short-circuit protected, and the internal frequency compensation ensures stability without external components.

Hello,
On FY2300H 25 mhz they are MC4558 under the aluminum radiator, I looked.

Regards.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 07, 2017, 02:37:15 am
I ordered mine (30MHz version) from Fasttech, they sell both 30 and 60MHz.
Paid 88$ (~75€), with no shipping fees or taxes added.
Can you look at the jumpers mentioned before? It would be most interesting to see the difference with the 60 MHz version.

I followed one of the traces, and its not a setting, but routing the VCO BNC connector to a different trace.
So that is why they are in pairs with one connected (scratchable) and one not connectedd.
Either the BNC plug is connected to one, or to another trace.

I believe something similar is true for the other pair, but something with USB/serial.

IOW, nothing to do with frequency models.
As stated, it would have been too easy if that was how it worked.

So if you want the 60MHz, just shell out an extra $20  :)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on November 07, 2017, 03:38:03 am
Hi all,

so I wasn't going to join up but I kept reading posts and watching some great videos from some slightly mad nerd and here I am  ;D

I have just taken delivery of a 30Mhz version Firmware 3.1 which as mentioned here already has an issue with a fairly unhealthy floating AC issue. To go with the ugly it is also very accurate in most other things.

It also has an issue with the DC offset having a consistently increasing error that appears to be firmware/maths related. 'Apparently' according to Feeltech this can be and has been fixed with more recent firmware upgrades but as that means shipping a newly delivered unit to mainland China and back it really isn't worth it.   :-- 

Trying to protect their software IP is I guess the major reason rather than enabling a simple programming header or upload system. If that is the reason then it is a poor one plenty of people out there love a challenge  :-+

First problem as discussed in this thread getting the ac floating voltage down. I was just going to drop an IEC socket in but changed my mind as there is plenty of case room for maybe fitting something else into the box as my electronics space is limited due to other toys. So Switch/Fuse and Socket adapter installed instead.

A quick check around the board, jacks and other metal plugs sees the USB case and all the BNC's sharing a common
 AC floating neutral. So like others I am far from happy plugging it into or onto gear until this is reduced.

Few components to add but the coffee needs roasting (part of what I do)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Mr. Scram on November 07, 2017, 04:20:42 am
Could you check the aforementioned jumpers?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on November 07, 2017, 04:54:53 am
I am assuming you mean the jumper from the power supply to main board?

All the terminals (including internal ground) are currently sitting at 32Vac at 50hz. I will be able to spend some more time looking at the board later.

Edit

went back a page. Gather you were now referring to the board jumbers J6, J10-12. They are the same settings as previously mentioned on mine.

2nd edit.

This makes for some interesting reading on the power supply design. https://www.eevblog.com/forum/projects/rm6203-switching-psu-controller/ (https://www.eevblog.com/forum/projects/rm6203-switching-psu-controller/)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 07, 2017, 07:04:03 am
I am assuming you mean the jumper from the power supply to main board?

Actually, I find the question on what "leakage voltage" you measure on the supply lines and/or BNC ground also interesting.
And maybe also how much the leakage voltage drops when grounding with a 1M, 100K, 1K resistor to ground. (iow, how current much the leakage can actually source)

As to your "where does the yellow one go" picture title? Is that a question?

If so, I saw someone claim that the 3 holes on the power board, shown pretty just below much dead-centre on your "Feeltech-stock.jpg" image (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/?action=dlattach;attach=367724;image), are ground connections.

And this guy (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1275521/#msg1275521) suggests maybe in stead of directly grounding it, using a Y cap. Maybe even a switch and a Y cap, so you can choose whether you want floating or fixed.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on November 07, 2017, 07:12:34 am
Based on a little reading on Class Y leakage and the RM6203 I am leaning toward connecting a 10nF cap from the secondary to earth. The idea of a hard switched internal ground to earth is an easy answer but it then places some operational limits on the device.

I do have an order to put into E14 in the next few days so I am going to add some 'proper' Class Y caps and swap out the current one and see if that helps too.

Fall back is to dump the cheapo power supply and fit a better one  :horse:

Just checked the underside of the board. Of the 3 holes in the pic the two outside are indeed connected to the virtual ground, the centre one has no copper around it.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: maddin on November 07, 2017, 07:33:52 pm
I found this interesting infos regarding Y capacitor:

https://electronics.stackexchange.com/questions/216959/what-does-the-y-capacitor-in-a-smps-do

If you don't like hard switche internal ground to earth the guy suggested using two capacitors, one from the output to mains earth and one from mains earth to the input.
Maybe the best way also for the FY6600. Anybody tried this solution ? What capacitors were used ?

Regards
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: wilhe_jo on November 07, 2017, 07:47:57 pm
For all of you searching for the CD contents....

http://www.feeltech.net/html/list_6.htm (http://www.feeltech.net/html/list_6.htm) brings you to http://www.feeltech.net/html/show_71.htm (http://www.feeltech.net/html/show_71.htm) which lets you download the RAR archive :)

vy 73
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: maddin on November 07, 2017, 08:39:02 pm
Included FY6600 PC Software V5.3.exe seems also be improved; no virus found  :D
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on November 07, 2017, 10:58:36 pm
10nF cap to from the secondary side of the Y cap to mains earth.

Result is a much better 9V at 50hZ. Some more playing needed but first COFFEE  :-+
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: battlecoder on November 07, 2017, 11:16:08 pm
After stalking the forums for a few days I decided to join the community.
Initially to thank all of you for sharing your tests and research on this device.

I think I'll be ordering one this week, and will try to contribute to this thread as soon as I get mine.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: bitseeker on November 07, 2017, 11:18:07 pm
Welcome to the forum, battlecoder!
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on November 08, 2017, 01:24:45 am
A little bodgetronics later  :o Instrument ground sits at about 3V ac maximum interestingly the Agilent is now reading it at 35kHz (checked on a handheld non rms reads 3.4V)  :-//

There is a little patch of unused board conveniently located right next to the secondaries of the transformer. 2mm screw, shakeproof washer and knurl nut as an earth point. A 10nF ceramic cap and a little heatshrink to each of the transformer secondaries.

Screen of the transient Earth to Virtual Ground below.

Out of ideas or improvements for now. Anyone else suggest an better option?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on November 08, 2017, 04:36:22 am
Scrapped all but the one Cap from the Y cap to Earth. The transients on the power supply were ugly and while the measured AC was down not a good solution I feel.

So out with my dodgy Hantek. What is interesting is that as soon as it is connected the before measured 7-9V ac all but dissipates. Earth to VG drops straight down to mV as per CH2. This is backed up by the Agilent in terms of DC offset of about -50mV Earth to VG and a spread of AC hash in measured the order of 150mV.

Frequency is bang on on both instruments at 10kHz (10,004 Agilent). Amplitude on the Hantek says 5.2V P-P, Agilent at 1.814 (5.13) for a figure of 5V on the Generator. Waveform looks nice and clean and Symmetrical. (with the single extra cap to earth).

Right now considering looking for a new power supply  :horse:

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: battlecoder on November 08, 2017, 04:48:38 am
Right now considering looking for a new power supply  :horse:

That seems to be the best way of dealing with this, unfortunately.
Other similar generators from Feeltech have this issue (e.g: The FY3200) and a DIY linear supply seems to be the best way of fixing. I do recall there was a video on youtube showing exactly this.
EDIT: https://www.youtube.com/watch?v=ML-lmuHoh-0 (https://www.youtube.com/watch?v=ML-lmuHoh-0)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on November 08, 2017, 05:56:08 am
Linear makes lots of sense.  :palm:

Dropped a 100k Bleeder Resistor from VG to Earth 2.5V ac and virtually nil DC as to be expected. Tried 500k and 1M but not much of a drop in AC. For reading Good enough for Keysight then good enough for Feeltech  :horse: http://powersupply.blogs.keysight.com/2014/11/why-do-i-measure-voltage-to-earth.html (http://powersupply.blogs.keysight.com/2014/11/why-do-i-measure-voltage-to-earth.html)

Back at this sort of voltage should make it safe for 'most' uses and users. Certainly a lot better than the garbage without it.

For my own use I am fairly happy now at this as when loaded with my just the DSO and bleeder/cap it drops way below these figures at 15mV AC and -50mV dc. Most likely won't look at a new supply at this stage.

***** Earth to VG is now at 20mV/div
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 08, 2017, 06:47:34 am
I was about to suggest you are overenginering, and should check what it can source and/or add a resistor, when I got notification of a new post.

Linear makes lots of sense.  :palm:

I don't know man. Did you see on the video that even with Linear he also still has an AC leakage of 12V (https://youtu.be/ML-lmuHoh-0?t=1600) Thats much more than what you have right now, despite his linear supply.

I think what you have now is a very good balance between simplistic and effective, and I will copy it.
The only think I might try is a 1M resister instead of a 100K, you said you tried but I did not quite understood the result.

I am not at home right now, otherwise I would be testing myself.  This thread seems to make it all very important, but I just did not pay attention before and everything seems to work. That is why I think that the 'floating' cannot really source any current, and we are being oversensitive.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on November 08, 2017, 07:01:53 am
I guess I have fried and seen enough things fried by ordinary design and attention to detail over the years. Haven't watched the video yet either.

Apart from a new supply it was always just a matter of 'some' filtering on the basis it is never going to be perfect but just where and what needed some educated blind guesswork. Given the bad start point and the low cost to big improvement well worth it for anyone with this supply. I will still fit up a different Y cap when they arrive.

Let us know what you find with the 1M, I have put the lid back on mine for now and will use it as is and have a proper play.  8)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: battlecoder on November 08, 2017, 07:20:54 am
I don't know man. Did you see on the video that even with Linear he also still has an AC leakage of 12V (https://youtu.be/ML-lmuHoh-0?t=1600) Thats much more than what you have right now, despite his linear supply.

I think what you have now is a very good balance between simplistic and effective, and I will copy it.
The only think I might try is a 1M resister instead of a 100K, you said you tried but I did not quite understood the result.

I am not at home right now, otherwise I would be testing myself.  This thread seems to make it all very important, but I just did not pay attention before and everything seems to work. That is why I think that the 'floating' cannot really source any current, and we are being oversensitive.
In defense of the mod suggested on the video, it was 12VAC but virtually 0 current (below 1 uA, apparently).

Anyway, I suspect that the optimal (or "good enough" solution) will be different for every user, depending on what they will be using the device for, and whatever lets them sleep at night.
For instance, I'll most likely follow the steps of beanflying and yourself, and simply use a bleeder resistor, because it's simple and apparently works a treat, but I'm sure a number of users would prefer to ditch the switching supply entirely and put a linear one in there.

I still hope that the unit I receive will not leak badly. It happened with the FY3200 that users were getting different voltage and current values for the "leak" (probably different hardware revisions, but could also be related to the difference in mains voltage and frequency between countries).
I guess it's like they say: "Your leakage may vary".
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 08, 2017, 10:47:03 am
It happened with the FY3200 that users were getting different voltage and...

Well, it also depends on your measuring equipment. Using 240V mains base (UK), measuring a 12V AC signal with a DMM that has a 10M impedance would imply a "leakage" of 200MOhm (ok, 190M), either restive or reactive. And there will always be some capacitance, so some reactive impedance.
Someone else measuring the exact same device with a DMM of 1M impedance would find 1.2V

... and current values for the "leak"

which is thus much more relevant. What current can the "leak" source. I plan to measure it as soon as I get home, but no-one else seemed to have supplied numbers here (maybe I have missed them). Which is why I suggested we should be a little more relaxed before bashing the power supply and adding deceased animal abuse symbols. At the very least until we have leakage current measurements.

Especially because the DC findings from @beanflying suggest a <10mV at 100KOhm measure impedance. Even though that was ground to virtual ground, it does suggest a better then 2400MOhm DC (non reactive, restive, please check my math) impedance on the mains-secondary-virtualground-ground path. 2.4GOhm ! Which if true means quite the opposite of the impression that this thread may be giving people.
 
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Specmaster on November 08, 2017, 11:07:31 am
I think that at the end of the day a decent linear power supply would certainly eliminate most of the leakage and if it really was a major concern, then it would not take too much to rig up a battery power pack option to completely remove the leakage to ground and thus the potential difference and problems arising from it? The current draw surely is not going to be that great is it?   
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on November 08, 2017, 12:44:47 pm
Nothing essentially wrong with switch mode power supplies. My 8 year old 15V 60A Switch mode Manson still runs at less than 5mV ripple in spite of plenty of kwality Capxom Caps. My Fixed 12V 20A bench supply (Chinese LED driver $25) is under 20mV and the VG on it is under 6V ac but using a little of what I have learned here I will have a look at improving it a bit too.

Dead animal flogging or not the power supply used here can and should be improved as it is sub standard for test equipment. It seems that if the same issue with earlier models has just flowed into this one then without making a little noise will likely see it continue in future production and models.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: ArthurDent on November 09, 2017, 02:48:52 am
After reading some of the other replies I have come up with a plan for the mods I want to try. First I measured the voltages on the stock power supply and measured +4.78, +13.6, and -13.8 which isn’t that close to the +5, +12, and -12 that it should be putting out - certainly not the best supply. Most good SMPS units have an adjustment that trims the +5 and the other two voltages are just kind of a ratio from the +5.00 so they aren’t as close but generally within +/- .2 volt.  Obviously the FY6600 worked with the existing P.S. but I wanted something closer so that meant changing supplies.

 I also wanted to change the timebase which is worse than 100 PPM and 50 Mhz so I figured I’d use a decent square wave 10 Mhz OCXO followed by a 50 Mhz passive bandpass filter to use the 5th harmonic from the square wave but CyberMaus mentioned the NB3N502 PLL IC that I didn’t know about and it looks like the perfect solution.  I didn’t want to incorporate a GPS into the unit (I have several different ones running 24/7) so decided to use an OCXO from a Trimble Thunderbolt that is fast warm-up and very stable. Power required at +12 cold is .7 amp so the existing P.S. wouldn’t have worked anyway. I’ll include a switch on the back panel so if I want to make use of the resolution the FY6600 is capable of at GPS or rubidium accuracy I can feed an external input to the X5 PLL. 

 So I’ve ordered a couple of NB3N502 PLL chips from Mouser that should be here any day now and I can get to removing the 50 MHZ SMD crappy oscillator and Frankenstein the PLL chip on the board in place of the 50 Mhz oscillator and put the OXCO on a small circuit board with a ten-turn pot to trim it on the back panel next to the switch and BNC for my external 10 Mhz reference.
 
 I have already changed power supplies and the one I chose is heftier than needed but is high quality and I had a few new ones I could use. The supply is a NFS40-7608 which is made by several venders and I bought the supplies I have from a surplus catalog at a good price.  So here is a photo of the power supply mounted in the case and working. I had to cut and splice the connector cable but it works as intended and I'll do an update once I get the rest of the modification done.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on November 09, 2017, 03:40:12 am
Fits Nicely :)

I gather looking at the photo you are running with Mains Earth directly to Virtual Ground?

May be there is a newer model of this supply available too. Some details and world wide vendors lists of that one https://www.artesyn.com/power/power-supplies/websheet/222/nlp40-series#stock (https://www.artesyn.com/power/power-supplies/websheet/222/nlp40-series#stock)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: ArthurDent on November 10, 2017, 09:58:42 pm
In my last post I said what I planned to do to modify the timebase for far greater accuracy and promised an update. Well the 3N502 PLL frequency multiplier chips I ordered came today so I tried to remove the 50 Mhz SMD oscillator and install one of the chips. It was kind of tricky because I don’t have a desolder tool so I made a small 4-tined ‘fork’ with offset legs made out of 1-watt resistor leads connected to the tip of my soldering iron that would heat all 4 pads of the oscillator simultaneously and it came off without any damage. As it works out, there isn’t much you have to do to install the chip and it worked perfectly once installed. I connected one of my GPS standards to the 10 Mhz input to the chip and got the expected 50 Mhz out of the installed chip. I then set the output of the FY6600 to 10.12345678 Mhz and measured it on my counter and the photo shows the output is correct to all 10 displayed digits.  Great!

The pins on the installed 3N502 chip that aren’t used I just bent out straight.  The resist on the ground plane under pin 7 had to be scraped so that pin could be soldered to ground. Pin 2 is connected to the 3.3 V pad on the board with a piece of #30 wire and a cap is connected from pin 2 to ground as recommended. The output on pin 5 is soldered directly to the pad underneath it because that run already has a resistor in series with the output that is also recommended in the spec sheet for the chip. The yellow 10 Mhz input wire was just tacked to pin 1 and that will be cleaned up in the final version. 

I still have to install the OXCO I’ll be using along with the associated BNC connector, trim pot, and switch but I had to test the timebase multiplier chip to see if it would do what I hoped it would and I’ll include another update when that’s done and the mods are all complete. I do want to thank CyberMaus again for finding the 3N502 chip because it works great. 
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on November 11, 2017, 02:02:21 am
Back from vacation and sitting in the post office was my F&6600 60MHz. Works fine and as expected. 50V AC on the output grounds... as expected. I'll add a grounded power connector and a Y cap/resistor pair to ground and call it a day. Nice to see so much interest in the unit.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 11, 2017, 02:36:41 am
I then set the output of the FY6600 to 10.12345678 Mhz and measured it on my counter and the photo shows the output is correct to all 10 displayed digits.  Great!
Correct 10 digits to 0.01Hz. That is great.  :-+ What absolute precision do you think your GPS have?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Mr. Scram on November 11, 2017, 02:39:04 am
In my last post I said what I planned to do to modify the timebase for far greater accuracy and promised an update. Well the 3N502 PLL frequency multiplier chips I ordered came today so I tried to remove the 50 Mhz SMD oscillator and install one of the chips. It was kind of tricky because I don’t have a desolder tool so I made a small 4-tined ‘fork’ with offset legs made out of 1-watt resistor leads connected to the tip of my soldering iron that would heat all 4 pads of the oscillator simultaneously and it came off without any damage. As it works out, there isn’t much you have to do to install the chip and it worked perfectly once installed. I connected one of my GPS standards to the 10 Mhz input to the chip and got the expected 50 Mhz out of the installed chip. I then set the output of the FY6600 to 10.12345678 Mhz and measured it on my counter and the photo shows the output is correct to all 10 displayed digits.  Great!

The pins on the installed 3N502 chip that aren’t used I just bent out straight.  The resist on the ground plane under pin 7 had to be scraped so that pin could be soldered to ground. Pin 2 is connected to the 3.3 V pad on the board with a piece of #30 wire and a cap is connected from pin 2 to ground as recommended. The output on pin 5 is soldered directly to the pad underneath it because that run already has a resistor in series with the output that is also recommended in the spec sheet for the chip. The yellow 10 Mhz input wire was just tacked to pin 1 and that will be cleaned up in the final version. 

I still have to install the OXCO I’ll be using along with the associated BNC connector, trim pot, and switch but I had to test the timebase multiplier chip to see if it would do what I hoped it would and I’ll include another update when that’s done and the mods are all complete. I do want to thank CyberMaus again for finding the 3N502 chip because it works great.
Can you tell us a little more about that sweet counter in the picture? The internet seems to be having trouble telling me about it. Is it a universal counter too?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: sorin on November 11, 2017, 02:56:12 am
http://www.es-france.com/pdf/pd_cnt81_81r.pdf (http://www.es-france.com/pdf/pd_cnt81_81r.pdf)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 11, 2017, 03:16:41 am
Identical to FLUKE PM6681 (https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwj8jruWx7XXAhVpIsAKHVReCD4QFggoMAA&url=http%3A%2F%2Fwww.testequipmenthq.com%2Fdatasheets%2FFLUKE-PM6681-Datasheet.pdf&usg=AOvVaw30eIFkJ864r2NdmPuRgvs1)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 11, 2017, 07:20:11 pm
Ok, so I do not think we will ever reach full concensus, but because I said I would, I went and measured current as well as voltage on a range of devices.
See attached table with AC values. DC was always 0 for all, so I did not even add it to the table, my basis is a 230V 50Hz mains

My conclusion: the FY6600 is indeed not the best (and I focus mostly on current) but in fact the Rigol DS1074Z is a lot worse. If you disconnect the earth.
And if you do connect them both to earth, again the Rigol is worse.

For the rest, the official Samsung USB is the best, by far, followed by my cheapo china linear bench supply.
In fact, the Samsung is so good, I had to doublecheck my DMM had not stopped working.
I measured some more cheapo supplies, but stopped writing them down, most are similar to the FY6600.

What I have learned from this is that if at all possible, I should avoid using my Rigol in "fake differential" mode by disconnecting the earth. I have done that in the past, have a special cable for it. I will modify that cable to also have the Y-cap (actually X2 because I have those) and 1M resistor, and use it sparingly. Yes, go ahead and scold me for it.
If only the math function (A-B) on the rigol was not so annoyingly slow.

The FY6600 will get a X2 and 1M, pretty much like beanflying, but also a switch so that most of the time it is simply fully grounded and not floating at all.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on November 11, 2017, 07:36:22 pm
I desoldered the mains leg of the Y cap and added a 10nf Y cap (that's what I have) from the mains side to the free leg of the original cap and then grounded the joined legs of the caps. Now getting 2.2VAC on low-z and a handful of uA (into the noise). This will be my default "floating" and then add a switch to fully ground the output.

Adding the grounded IEC was easy as the back panel is very thin and a dremel cuts through it like a knife through butter. Note that the original cable and socket are not even polarized.  ::)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: bitseeker on November 12, 2017, 05:50:54 am
For the rest, the official Samsung USB is the best, by far, followed by my cheapo china linear bench supply.
In fact, the Samsung is so good, I had to doublecheck my DMM had not stopped working.

That is really good. What was the arrangement in their supply (or is it inconveniently welded shut)?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: ArthurDent on November 12, 2017, 04:03:25 pm
Well I believe I’m pretty much finished with the modifications to my FY660.  I’ll answer a couple of questions that popped up concerning my equipment or what I did then show some photos of the finished product.

As to testing this FY6600 using my GPSDOs as standards and how ‘accurate’ they are, what I have is two 26 dB gain GPS antennas at the opposite ends of my roof that drive two GPS distribution amps to allow me to run and test multiple GPS receivers simultaneously. I had sold about 200 Trimble Thunderbolts GPSDOs in the past which is one reason for the setup I have. As to the accuracy of my GPS system, long term it is about as accurate as the GPS source and short term the 10 Mhz output stays within a couple hundred PPT worse case. A 25-year old rubidium standard I have has better short term stability but a couple of my crystal standards have less noise and very good short term stability.  For most stuff all this is far more accurate and stable than I would ever need but you gotta have neat toys, right?

I have carried the physical ground from the power cord right through on the FY6600 and almost every piece of equipment I own comes grounded that same way.  The only place I ever had to be concerned about ground loops was a place I worked where we tested (sometimes very destructively) products with high voltage/current pulses a few microseconds long and with current spikes of 20,000 amps. Even with the heavy copper bus bars for grounding we had to pay careful attention to using a common ground point so the readings we took weren’t influenced by the voltage drop across these massive copper bars.

The Fluke/Philips 6681 or Pendulum CNT-81 counters I use are excellent counters that let me display the 10 Mhz frequency I am generally interested in directly to 10 digits (2 decimal places) in one second or by using the built in math function to 5 decimal places in 10 seconds which is perhaps giving me more resolution than accuracy, but not by much.  I have a saved function on the counters that subtracts 9,999,999hz from the 10,000,000 Hz signal. If the test 10 Mhz input is exactly equal to the 10 Mhz external reference from my standards, in 10 seconds the counter will display 1.00000 or 5 decimal places (ignore the 1, it just helps the display format).  I generally also feed the same signal into my scope which is externally triggered by my same external 10 Mhz standard and check for drift at 2 ns/div giving me a visual indication as well. 

Why the 50 Mhz timebase in the FY6600 bugged me so much is that the frequency output can be set to 14 digits but the timebase was only accurate to about 5 digits. Also it wasn’t stable or trimable. With the top cover off the FY6600 and the output set to 10 Mhz and displayed on a scope triggered from an external 10 Mhz standard, if you just blew across the 50 Mhz oscillator you would see the frequency change rapidly and drastically. The OXCO I built into the FY6600 looks very good after warm-up and I can always use an external 10 Mhz reference if I want more accuracy and stability. Here is what the frequency output set to 10 Mhz (and the oscillator) looks like on warm-up after having been trimmed previously.  Start-up  -200hz ; 3min +.05 ; 20min +.01 ; 30min onward +/-.005hz or +/-5 at the 11th digit. Because the rear switch on the FY6600 turns the power supply on/off and the front panel power switch just puts the main board in standby mode, if you leave the rear switch on the OXCO is always powered and you eliminate the warm-up period. Generally the longer a good crystal oscillator is left on the more stable it becomes and some of the better standards I have take over 2 weeks to really stabilize. Using a TXCO with low power supply current requirements instead of an OXCO like I used could allow you to use the existing SMPS with some loss of accuracy and stability if you want to keep the modifications simpler.

The photos show the back panel with the added BNC connector for 10 Mhz ext ref in, the int/ext switch, and the recessed trimpot. Unfortunately installing these parts covered some of the text on the rear panel but I can live with that. Perhaps a small SMA connector and a smaller switch would be a better choice. The inside photo of that area shows how the OXCO is mounted on a phenolic board that was hand wired and that board mounted on the aluminum bracket held to the rear panel by the BNC connector and the switch mounting hardware.  There are a few resistors near the switch to adjust the levels the PLL chip sees from the OXCO and the ext ref and I may add a buffer to further protect the PLL chip from possible input spikes from any ext ref. The 3rd photo shows the sub-miniature Teflon coax I securely soldered to the ground plane near the PLL chip and the center wire soldered to the input pin. It was important that there was little strain on that cable so it wouldn’t rip off and break the input pin off the PLL chip.
 
Sorry for being longwinded but I hope this explanation helps others decide what they want to do and what is important to their needs.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 12, 2017, 06:28:13 pm
So your stated credentials are such that I have to assume you know your way around time standards. So please consider these questions as education for me, and not as questioning your setup.

As to the accuracy of my GPS system, long term it is about as accurate as the GPS source and short term the 10 Mhz output stays within a couple hundred nanoseconds worse case.

So a couple of "a couple hundred nanoseconds" does not actually sound very precise. When I read the NEO-M8N specs, it mentions 30ns, but graphs in the application note (https://www.u-blox.com/sites/default/files/products/documents/Timing_AppNote_%28GPS.G6-X-11007%29.pdf?utm_source=en%2Fimages%2Fdownloads%2FProduct_Docs%2FTiming_AppNote_%28GPS.G6-X-11007%29.pdf) show this to be -17/+13ns on a 1pps pulse, mostly due to quantification of the internal 48MHz TCXO.

So am I interpreting this wrong, or is your GPS older and not very precise when compared to recent GPS modules?

The application note also lists other precisions, like 0.062ppb frequency stability (maybe very long term?) and a 4E-9 (4ppb) Allen deviation at 1 sec, and I cannot make heads or tails of the sub second precision expressed in spectrum graph, though I do see it is based on a 24MHz signal with only 3.046ns jitter.
Which I am hopefully interpreting as possible to get 3ns precision, if you stay with an integer division of 48MHz timepulse, which is also advised in the summery of the application note.

Could I tempt you to read the application note, and give me your though on it.


I could not find a local source (only potted modules for drones), so am waiting for china, but alas, ebay kicked out my seller, so I had to re-order, and wait even more.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: ArthurDent on November 12, 2017, 07:28:50 pm
Cybermaus, when you say: "So a couple of "a couple hundred nanoseconds" does not actually sound very precise." you are correct. I have corrected that reference in my previous post after reading your comment. The line should have read "PPT" for parts per trillion, not nanoseconds. Generally the time instability is 2 ns or less. Sorry for the screw up and thanks for picking it up. Here is a 10 hour graph that shows the 10 Mhz output stability of one of the Nortel/Lucent GPSTMs that I modify.
Title: Re : FeelTech FY6600 60MHz 2 canaux VCO fonction générateur de signaux arbitraires Signal
Post by: Ebel0410 on November 12, 2017, 07:46:58 pm
Just ordered on eBay a TCXO 25MHz and 5x ICS511M for a total amount of 10$.
This TCXO is announced better than 1ppm (it means 0,0001%) and it can be trimmed +/-5ppm around 25.000MHz.
I hope that the ICS511 (used as frequency doubler) will not introduce too much jitter.

The frequency tested on the stock CXO 50.000 XTAL in my FY6600 is 50.000.492Hz,

I'll keep you posted when I'll receive them.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on November 13, 2017, 12:08:01 am
Following the lead of others, I am also looking at building a TCXO and PLL with maybe an optional 10MHz input. Might be a nice add-in board kit for someone to design. Apart from the PSU, the timebase is the other major weak part of this device.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on November 13, 2017, 02:20:56 am
And to think all I wanted was a 'cheap' signal generator that worked  :palm:

Nice work on the mods all  :clap:

off to look at 'cheap' spectrum analyzers next .........
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on November 13, 2017, 02:46:10 am
And to think all I wanted was a 'cheap' signal generator that worked  :palm:

Nice work on the mods all  :clap:

off to look at 'cheap' spectrum analyzers next .........

Yeah... to be fair, I knew about the PSU going in and its not an expensive nor time consuming mod. The poor time base is a disappointment but the added cost is not huge, although it may require more time to complete. I hope Feeltech is paying attention here. They could have a real killer AWG for the money with a few small changes.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Vytautas on November 13, 2017, 06:18:34 am
Hello, everyone,
I just finished my modifications of the fy6600:

1. Replaced the power supply with a linear one. The voltage was increased to +-15V because +-12V does not give enough headroom for the output amplifier to be able to go all the way up to the maximum amplitude of 20Vpp (or, rather 10Vpp into 50 Ohms).

2. Then, I replaced the dodgy output amplifier op-amp. The original one is an unknown 30021. At first I thought this is a dual variant of the single THS3001 but some guy has inquired about it from Texas Instruments and they replied that they do not manufacture such. So, who knows what FeelTech uses here. Therefore, I chose to replace it with two single THS3095 op-amps. Thankfully, the board has places ready for them, with all bypassing and anything needed. Beauty! This change (and, of course, new +-15V power supply) now lets the generator output full 10Vpp into 50 Ohms with no distortion (the original 30021 would go only to somewhere above 7Vpp and heavily clipped, and increasing power supply did not do much).

3. Some other mods - changed the output amplifier heatsink to a larger one, added a small heatsink to the FPGA, added a 12V fan (I run it from 8V, so it is quiet; a separate power supply for the fan, because connecting a fan to the 5V or 15V rail will affect the performance of the generator).

Here is the list of pictures:
1. Original board with the dodgy 30021 op amp.
2. Modified board with two THS3095 op amps.
3. 1M sinewave at full amplitude of 10Vpp into 50 Ohms termination.
4, 5. 1M sinewave at 5Vpp and 20Vpp. In both, harmonics are -60dB down. Beauty!
6. Modified internals.
7. 1M sinewave AM modulated with the 1K signal from the second channel.
Cheers!
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on November 13, 2017, 04:17:48 pm
Nice work but won't the presence of a fan affect the 50Mhz time base?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 13, 2017, 04:56:51 pm
Just picked this up from the manual:

"Use the process, long press the parameter adjustment knob (OK button), you
can quickly save the instrument output parameters, the next boot,
automatically load the saved parameters."

And it actually works, except (Feeltech, if you read, please take note!)
- There is absolutely no feedback that the save has happened. No beep, no message.
- It saves the waveform, but it does not save if the channels are active or not. I feel if for example Ch2 is inactive during save, it should also be inactive after reboot.

Still, a useful bit of info I thought.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 13, 2017, 05:08:49 pm
Checking @Vytautas: Indeed, 20Vpp at high-z is OK, but at 50R is at 7.x V only, and looks to have very rounded domes.

But is that due to the 12V supply (actually about 14.8), or due to the "donky" OpAmp? It must step up the 12V to 22V anyway, because at high-z I can even add 1.5V offset before clipping starts, getting a nice shape up to 21.5V and -21.5V

Also, 20Vpp at high-z, it looks perfect sine (eyeballing) up until 3MHz or so, then it starts to visibly distort. Hence I was reading the manual to check if the 20Vpp was supposed to be up to what frequency. But it automatically steps down to 5Vpp at 20MHz. I wonder if @Vytautas can check that with his new OpAmps.

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Vytautas on November 13, 2017, 06:17:40 pm
Hi, cybermaus,
The problem is mostly due to the "30021" op amp. As you say, it is only just above 7Vpp into 50 ohms. And I had tried at first powering the generator from my lab supply with +-15V. The improvement was miserable if any. So, it must be the op amp.

With the THS3095 the generator easily outputs 20Vpp (10Vpp into 50R), no problem. Still, if to be picky, the behavior of the THS3095 is in line with what the manufacturer shows in their datasheet for the component. The pictures bellow are taken from the datasheet. At high frequencies, as those graphs also show, I see some distortion (not clipping though but exactly the same as manufacturer graphs show). The manufacturer suggests properly paralleling two op-amps for each channel (second picture) to remove most of the distortion. That is what major manufacturers, like Siglent, and others do in their designs. For the sake of interest, I might have a look at that later (accidentally, I do have two more THS3095s in my drawer). By the way, Texas Instruments have recently introduced a new power opamp - THS3491. If what they say is true, that one is a real beast with unmatched performance. But they do not have them yet.

Sure, the generator steps down to 5Vpp at 20MHz. But that is to be expected. Normal behavior. Difficult to achieve frequent swings at high voltages.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Vytautas on November 13, 2017, 06:23:56 pm
Nice work but won't the presence of a fan affect the 50Mhz time base?

Why would you think it would?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on November 13, 2017, 06:29:30 pm
Nice work but won't the presence of a fan affect the 50Mhz time base?

Why would you think it would?

A previous poster has noted that just blowing on the oscillator changes the frequency. It appears to have poor temp stability.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 13, 2017, 06:33:19 pm
Sorry, my question was not properly constructed:

"Also, 20Vpp at high-z, it looks perfect sine (eyeballing) up until 3MHz or so, then it starts to visibly distort. Hence I was reading the manual to check if the 20Vpp was supposed to be up to what frequency. But it automatically steps down to 5Vpp at 20MHz. I wonder if @Vytautas can check that with his new OpAmps."

I did not mean to ask if it also stepped down to 5Vpp, because that is kinda obvious.
Instead I meant: Can you check with your new Op-Amps if the range from 3MHz to 20MHz in high-z is still so horribly distorted, or did that improve with those op-amps.

And now I have a new question, based on your graphs: the old op-amps had a pretty good high frequency signal at lower voltages. @Ebel0410 showed -44dB
Are you saying that is now worse with your new opamp, or are those errors only at full voltage swing?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Vytautas on November 13, 2017, 07:26:26 pm
Rest assured, the performance with the new op amps is way better.
Here are some of the photos - 3MHz, 20MHz, 30MHz, 60MHz - at maximum possible amplitude. Left is High-Z, right - 50 ohms terminated.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on November 13, 2017, 07:41:43 pm
Do the upcoming 3491's share the same footprint? Might make a good future upgrade.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Vytautas on November 13, 2017, 07:48:42 pm
Yes, they are a direct pin compatible replacement for the 3095 with performance figures hard to believe. Lets see. They certainly should become a worth replacement.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Vytautas on November 13, 2017, 07:51:32 pm
Here Texas Instruments have a comparison table:
http://www.ti.com/product/THS3491 (http://www.ti.com/product/THS3491)
Better BW, better slew rate,  better noise performance.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Vytautas on November 14, 2017, 10:41:16 am
Hi, cybermouse,
Just to be sure, I tried powering the modified board with new op amps from the original switching power supply. Sure enough, the waveform is clipped and heavily distorted in high amplitude settings. So, the voltage from that supply is not enough. +-15V is a must (no wonder, this is to be expected).
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 14, 2017, 10:56:17 am
Ok, noted. Not sure how mine does the high impedance 20Vpp then, but noted anyway.

So just to make clear: You state to have a +-15V linear transformer, but are feeding linear regulated (79/7815, so +-15V) to the device? Or are you regulating higher, using the  sqrt(2)*15V=21V peaks?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Vytautas on November 14, 2017, 11:36:06 am
Ok, noted. Not sure how mine does the high impedance 20Vpp then, but noted anyway.

So just to make clear: You state to have a +-15V linear transformer, but are feeding linear regulated (79/7815, so +-15V) to the device? Or are you regulating higher, using the  sqrt(2)*15V=21V peaks?

I am using a 20V linear tranformers (more precisely, two 9,8V windings of the transformer in series) and regulating with LM317 and LM337 regulators both for +-15V and +5V (these, actually, have a better noise performance than 7915/7815s). The voltage stays +-15V under load, naturally.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Vytautas on November 14, 2017, 12:11:18 pm
By the way, this is the schematic of my +-15V rail. It is, sure, an overkill. But I like overkills  :palm:
16V AC enough to drive it. Or, alternatyvely, two 15 AC windings could be used for full wave rectification.
Cheers!
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 14, 2017, 12:53:01 pm
 :wtf: I now have additional questions.

You seem to have it working, so I must be missing some trick.
How are you getting 16V peak out of 9.8Vrms?
What are those 100R R1,R2, C5,C6 doing there, are they not dropping voltage even more?
Also, what is that 10R R7 doing?

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Vytautas on November 14, 2017, 01:02:05 pm
Not out of 9.8V but out of 19.6V. As I mentioned the double 9.8V windings are connected in series to get 19.6V. Both transformers you see in the image have DUAL 9.8V windings (and other windings which I use for the +5V rail).
Concerning the components, if you want to read more about a similar supply design, welcome to see here:
http://sound.whsites.net/project05b.htm (http://sound.whsites.net/project05b.htm)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 14, 2017, 01:08:19 pm
Ah! I stupidly assumed the other one was the 5V trafo.

I read you had them in series, but even that I had read as in series and centre tapped.
I guess your unique transformer selection means they all come from the leftover bin.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Vytautas on November 14, 2017, 01:21:12 pm
Of course, left over. If I were richer, I might have well purchased a fancy Agilent or Tektronix generator  :o
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on November 15, 2017, 01:35:02 am
My x1 y1 Vishays turned up today. Same esr for the stock and vishay and in the end the same sorts of voltages to mains earth.

I went back over the 1M, 470k, and the 100k resistors from virtual ground to mains earth and the 100k as before gave the lowest result at under 3Vac again.

So nothing new I guess. Must look back at the better quality mods now  8)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on November 15, 2017, 03:34:37 am
Firstly I know ZERO about Cyclone chips but has anyone got any thoughts on the possibility of downloading and or upgrading the firmware without this ridiculous 'must be sent back to the factory for upgrade'?

My reason is this seems this version 2.9 is consistantly higher on output than indicated on both DC offset and AC waveforms at least. I haven't looked more comprehensively at the other waves and such or pushed the limits of the unit.

My Hantek Scope backs up my Agilent and double checked against one of my Victors on this.

5Vac p-p (1.768 RMS) 50hZ indicated (Victor 86B 1.842 49.98Hz) (Agilent 1.8396 50.001Hz)
5Vac p-p (1.768 RMS) 1kHz indicated (Victor 86B 1.826 0.999kHz) (Agilent 1.8394 1.00004kHz)
5Vac p-p (1.768 RMS) 10kHz indicated (Victor 86B 1.128** 9.99kHz) (Agilent 1.835 10.0004kHz)

The real problem becomes when you add a small DC offset to it as per the picture below.

Same series of Voltages and Frequencies as above with a "2Vdc" offset just with the Agilent. Not sure if the small drop off in AC voltage is power supply or maybe meter waveform integration related?

50Hz  1.798ac 50.002Hz 2.2215Vdc
1K 1.797ac 10.00004kHz 2.2212Vdc
10k 1.793ac 10.00004kHz 2.2206Vdc

Even when I drop the Amplitude and Frequency off to Zero it still reads 2.178Vdc (ac circa 0.06mV) apparently this is a firmware calibration issue hence the first question.  :-//
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 15, 2017, 06:43:10 am
Measured my values to compare, on a 3.1 version
Note that if these devices are calibrated, that would also be in the flash, and more relevant then the version.

I do not have such a nice bench meter, but here is what I measured:

5Vpp + 0Vdc, pretty consistent for 10KHz 1KHz 50Hz
5.3Vpp (scope)
1.77Vrms on my trueRMS BXM9BT
1.77Vac on my VC9808+

5Vpp + 2Vdc and 0Vpp+2Vdc
2.15Vmid (scope)
2.14Vdc on my trueRMS BXM9BT
2.13Vdc on my VC9808+

0Vpp + 4Vdc
4.34Vmid (scope)
4.33Vdc on my trueRMS BXM9BT
4.30Vdc on my VC9808+

So, over the board +7% on DC offset, but Vpp was pretty good.
Slightly better I guess, but is it version or calibration? They may have skipped calibration in mass production, and offered you calibration (on top of new flash)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on November 15, 2017, 08:53:48 am
Not sure if I feel better or not now knowing mine is not the only one out of step with accuracy  :-\

Interesting to see if anyone with 3.9 or more recent firmware gets better or similar. If similar then I guess it's time to go chasing a hardware solution?

As a fallback not that it is ideal there is several regular waveforms needed I planned to program anyway so I could always preset "known" voltages for these against  my Agilent or CRO.

For the sorts of work I am doing which is low voltage and sub 1Mhz DC the timebase issue doesn't concern me at this time but cool creative stuff still :)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: ArthurDent on November 16, 2017, 03:54:59 pm
(Note: I edited this post after don.r pointed out I had misread the part number mentioned as a future replacement IC. The rest of what I posted regarding possible noise imposed on the +/- supplies should be correct.)

On replacing the mystery dual op amp with 2 THS3095D single op amps as Vytautas has done, I just ordered 2 from Mouser Electronics. They still aren't real cheap at $10.64 US each but still worth the cost if you want to upgrade the output to get lower distortion at the higher voltage the FY6600 is capable of.

I'm not sure if these faster chips will improve the rise time on square waves or not but they won't hurt. Also I'd assume the THS3095D chips draw a little more supply current and may impose some added load and noise on the +/- supplies feeding them and means you'll want to use a +/-15V supply with higher output current capacity instead of the existing +/-12V supply to get the full benefit of the new chips. I'll check the a.c. voltages on the bypass capacitors next to these chip with the scope once they are installed to see if there is any noise cause by the higher current drain of the THS3095D chips necessitating more capacitance needed across the existing capacitors and report what I find, probably in about 1 week.   
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on November 16, 2017, 04:01:33 pm
The THS3091 is an old chip. The new ones are the THS3491.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: ArthurDent on November 16, 2017, 04:13:51 pm
Oops, I misread. Should pay more attention next time. Thanks for pointing it out.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on November 17, 2017, 01:28:34 am
Output Voltage Calibration

Seems the output voltages are not in fact firmware set. After taking a careful photo and tracing the board a bit the following pots can be twirled  :scared:

As labeled. They are very twitchy so I might look at hacking some 10 turn pots to replace them.

W5 CH1 DC offset adjustment
W3 CH2 DC offset adjustment

Easiest cal method. Set Frequency to 0 and ampl to 0. Set offset to 10V and tweak. There is still a bit of non linearity so some more looking at resistors or for voltage references is in order.

W26 CH1 AMPL P-P adjustment
W16 CH2 AMPL P-P adjustment

I found setting these to 10V P-P gave me about the best linearity across the range. At 20V P-P low Amplitudes were out. So like the DC a bit more looking required. Tested from 50Hz to 100kHz and no real amplitude change.

This gets it within 1-2% across the range instead of the up to 10% I was reading  :-+

So what does it mean - less than ideal calibration and testing in the factory I suspect?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on November 17, 2017, 05:04:23 am
W1 changes the CH2 low end DC calibration. Set 100mV and tweak seems to work best

W2 is the same but for CH1.

They do also effect the top end DC calibration by a small margin so a little to and fro with W3 and W5 is needed to get the best result across the range.

I have exhausted what coffee can do for today. Time for a BEER  :popcorn:
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Diabolo on November 17, 2017, 05:48:16 am
Hello,

I own the FY2300H 14 bit 250 MSa / s and had to open the generator to adjust the output levels when I received it. Under the radiator FY2300H there are IC 30021 and MC45558, and also the free tracks U21 and U22 for soldering of 2 IC TH3091 after remove IC 30021.
The THS3095 IC has a power-down spindle that is not useful since not connected on FY6600 et FY2300H Feeltech.
 
Buy THS3091 low price :
- https://fr.aliexpress.com/item/1pcs-THS3091DR-THS3091-SOP-8/32824185282.html?spm=a2g0s.9042311.0.0.SpCn6H


Regards,
Diabolo
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 17, 2017, 06:31:19 am
I have exhausted what coffee can do for today. Time for a BEER  :popcorn:
Well earned.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on November 17, 2017, 07:41:47 am
And to Feeltech, you shouldn't take our criticisms of the current generation of product to heart to much. There is a reason we are working on our units the basic ideas and features we like are worth persisting with and if it helps you to improve future models then great  :-+

So far mine for some time and under $4 of components is a much improved item. Some of the others upgrades would certainly add a bit to your costs but for most users not required I feel.

Jump back in we don't bite to much  ;)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: sorin on November 17, 2017, 10:54:05 am
Output Voltage Calibration

Seems the output voltages are not in fact firmware set. After taking a careful photo and tracing the board a bit the following pots can be twirled  :scared:

As labeled. They are very twitchy so I might look at hacking some 10 turn pots to replace them.

W5 CH1 DC offset adjustment
W3 CH2 DC offset adjustment

Easiest cal method. Set Frequency to 0 and ampl to 0. Set offset to 10V and tweak. There is still a bit of non linearity so some more looking at resistors or for voltage references is in order.

W26 CH1 AMPL P-P adjustment
W16 CH2 AMPL P-P adjustment

I found setting these to 10V P-P gave me about the best linearity across the range. At 20V P-P low Amplitudes were out. So like the DC a bit more looking required. Tested from 50Hz to 100kHz and no real amplitude change.

This gets it within 1-2% across the range instead of the up to 10% I was reading  :-+

So what does it mean - less than ideal calibration and testing in the factory I suspect?


I dont think so.
In my opinion W5, W3, W26, W16 are used for Differential OpAmp compensation.
More info here (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1343034/#msg1343034).

The responsible components for the DC offset are IC7 & IC8, 12bit DAC [MCP4822E].

(https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/?action=dlattach;attach=367323;image)
Thanks to Ebel0410 (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1351221/#msg1351221) for the image.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on November 17, 2017, 01:21:09 pm
And if we continue your logic the DAC's are actually controlled by the Cyclone so that is what actually controls the DC offsets not the DAC's.

As we currently have no way into the micro we have no control over the DAC's and their output calibration so the only control over the outputs is by controlling the opamps or additional analog circuitry after the DAC's to my way of thinking.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 17, 2017, 04:36:01 pm
In my opinion W5, W3, W26, W16 are used for Differential OpAmp compensation.
More info here (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1343034/#msg1343034).

The responsible components for the DC offset are IC7 & IC8, 12bit DAC [MCP4822E]

My original thinking was also that those low-speed DAC's do slow amplification and offset levels. However, one cannot argue with results, and beanflying seemed to got that.
It may have been a side-effect of something else, but can you explain what in your view the differential opamp actually does, and what would have been de-tuned when beanflying changed those pots?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Diabolo on November 17, 2017, 04:49:48 pm
Hello,
W1 and W2 are the settings that I had to adjust equalize the amplitudes when receiving my FY2300H
I ordered 2 IC THS3091 to improve (?) the signals and also to spread the heat dissipation on 2 IC and not on 1 IC alone.

Regards,
Diabolo
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on November 17, 2017, 10:53:31 pm
Coffee Morning Sunshine and a pleasant 22 degrees in the shack  :-+

Just ran a series of tests on Ch1 and 2 after yesterdays tweaking. A few of the 1Mhz voltages must be pushing either the Feeltech or the Agilent a bit so they are out. Will boot up the scope later and have a look.

Just checked the Agilent is rated +-4% from 100-300KHz and Typical error at 1MHz of 30%  8)



Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on November 18, 2017, 02:41:03 am
Coffee Morning Sunshine and a pleasant 22 degrees in the shack  :-+

My lab in the garage is 2 degrees this evening.  :--
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Mr. Scram on November 18, 2017, 03:00:49 am
My lab in the garage is 2 degrees this evening.  :--
Just give your office chair a push and you'll see the other 358 degrees swirls by in no time.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on November 18, 2017, 03:07:34 am
Coffee Morning Sunshine and a pleasant 22 degrees in the shack  :-+

My lab in the garage is 2 degrees this evening.  :--

I remember being in Chicago in early November once when the NW wind came in out of Canada wasn't pleasant at all.

Building Voltage references in shorts and a Tshirt at present :-DD
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on November 18, 2017, 03:19:30 am
Coffee Morning Sunshine and a pleasant 22 degrees in the shack  :-+

My lab in the garage is 2 degrees this evening.  :--

I remember being in Chicago in early November once when the NW wind came in out of Canada wasn't pleasant at all.

Building Voltage references in shorts and a Tshirt at present :-DD

I shouldn't complain really. I just spent two weeks in Hawaii. Maybe that's why 2 degrees feels like -20 right now.  ;D
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 18, 2017, 02:41:41 pm
So, I read out the 25 spi flash Winbond 25Q16BVSIG flash chip.
Content attached. Did cursory review, some patterns, some empty space, some high density data.

What I would like is if someone with a 2.9 or 3.2 or even also 3.2.1 model to also do this, so we can check if indeed there are only settings in the FLASH.
Presumably waveforms are all the same between 2.9 and 3.1, so if there are only very little changes, it would point to calibration.
Similar for 30MHz models.

However, (should not need to mention it on this forum, but do so anyway) this is at your own risk. I am not responsible for you messing up your device.




Please note that I think the flash is not all the firmware. The display board ARM SoC also has internal flash. It is quite possible these 2 are not always compatible when different versions.
But waveforms is definitely be in the flash, likely also the Cyclone, but probably not the UI programming or the user settings.
Posted some more on Winbond flash memory map here (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1353950/#msg1353950).

Used a cheap CH341A clone SPI programmer (https://www.ebay.com/itm/172265718620) . See this video (not mine)
tool download link in video (https://drive.google.com/file/d/0ByEQKtsOckWBUVBqajZOUGtLcnM/view)

Warning: not all CH341A clones are 3.3V (https://www.eevblog.com/forum/repair/ch341a-serial-memory-programmer-power-supply-fix/). Ensure you have one that can be properly set to 3.3V.
Note that depending on the clone, you need to pay attention to chip orientation. Both the program icon and the video instruction did not match correct orientation for my programmer clone (I have the exact one of the link above, but there seem to be 2 or 3 more variants.
So look at the silkscreen, use the 25x position for this Winbond chip.

this video (https://www.youtube.com/watch?v=L0ChYNwunUE)

FY6600 Programming header (Cyclone header):
1CLKGND2
3DONEVcc4
5/CFG/CE6
7DO/CS8
9DIGND10

Pinout mapping:
JTAGFPGA (https://www.altera.com/content/dam/altera-www/global/en_US/pdfs/literature/dp/cyclone-iv/ep4ce6.pdf)FLASH (https://media.digikey.com/pdf/Data%20Sheets/Winbond%20PDFs/W25Q16BV.pdf)
1126CLK
2 4GND
392 Conf_DonePulled up with 10K
4 8Vcc
514 nConfigWarning, low can clear the FPGA? Is pulled high by 10K
621 nCEWhen high FPGA disable in tri-state
7132DO / Data0
8 1/CSWhen high FLASH disable in tri-state
965DI / ASDO
10 4GND

To program Cyclone IV:
- Instructions to be interpreted by a Cyclone expert, being someone else then me
- Keep /CS from Winbond HIGH to disable Winbond Flash
- Pins CLK, /CFG,/CE, DO, DI, DONE have Cyclone functions DCLK, nConfig, nCE, Data0, ASDO, Conf_Done
- Use ByteBlaster II or USB Blaster 10-pin header

To program Winbond:
- Ensure 3.3V or lower programming level
- Connect GND, but Vcc is probably not needed (already fed from FY6600)
- Warning, never make /CFG or nConfig from Cyclone low, as this may clear the Cyclone (https://www.altera.com/content/dam/altera-www/global/en_US/pdfs/literature/dp/cyclone-iv/pcg-01008.pdf)
   maybe best not to even wire the /CFG pin.
- Keep /CE from Cyclone HIGH to disable the Cyclone
- Connect CLK, DO, DI, /CS to SPI programmer (or keep CS low)
- WP and HOLD are already connected high on the FY6600 board

Winbond Cable FY6600-JTAG to DIL-8 emulated chip footprint:
- Loop /CE to Vcc. /CE is normally 10K to ground, so must be lower impedance to Vcc
- Connect GND, CLK, DO, DI, /CS to SPI programmer
 
When you connect the cable the Cyclone IV FPGA will not start up because nCE is looped high to Vcc. Not even if the other end of the cable is not connected. But the FY6600 does does show its logo. I guess the logo is burned into the screen driver rather then driven by the FPGA

Cable for Flash read/write
WARNING: I wrote this down incorrectly and swapped in 4 and 6. Sorry. Correct now.
JTAGDIL-8
16
24
3
4 loop to 6
5
6 loop to 4
72
81
95
10





Edit: While analyzing the firmware, I made some interesting new finds:
More detailed info here (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1353950/#msg1353950), but a summery:

The programming header is a standard Cyclone USB Blaster II header, see newly attached image.
Also, I now believe the first x05ffff bytes of the flash are the Cyclone configuration bitstream. The cyclone itself reads this without the intervention of a CPU, as shown in this document. (https://www.altera.com/en_US/pdfs/literature/hb/cyclone-iv/cyiv-51008.pdf)

Flash structure:
0x000000 Cyclone bitstream
0x060000 Most build in waveforms (not in 1:1 mapping) (the ones repeating in Arb).
0x100000 Arb1~64 in blocks of x4000 bytes (first 32 a repeat of 0x060000)

There is likely no user settings or calibration in the flash. I changed settings, and reread, and nothing was changed.
So user settings are likely stored in SoC on the display board, which controls the Cyclone by simply serial commands.

In other words, the SoC has the User UI firmware, that is not stored in the Winbond flash, and we need to retrieve that too.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on November 18, 2017, 05:08:38 pm
Hey Cybermaus, you did a great job !
Day after day we're moving forward to the Graal...

Now we need the help of someone who's is talking FGPA and hacking fluently.
I read that for example and it was really awesome (http://blog.weinigel.se/2016/05/01/sds7102-hacking.html (http://blog.weinigel.se/2016/05/01/sds7102-hacking.html))
, that man would be very helpful to move one step higher.
Christer christer@weinigel.se , if you feel inspired, don't hesitate  :P
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 18, 2017, 06:33:59 pm
Well, if you want that kind of help from someone not already part of the FY6600 community, you may need to gift them a device (in the form of a dropship) with no expectations attached.

But more to the point: his Owon has a SoC CPU controlling the FPGA. A CPU typically works from a file system, with a bootloader and mountable partitions.
And in fact the CPU feeds the FPGA the configuration bitstream, so that FPGA config is a readable file in said filesystem. Its what your android does when it upgrades its radio/modem sub-firmware.


In our case, there is no SoC, its only the FPGA. And thus it is not programmed through the CPU, but directly from the header, as evident by the pins on the header.
This is why we cannot upgrade via USB. While you can configure a simple virtual CPU core on an FPGA, you cannot use programming on that core itself to reconfigure itself.
Also as far as I understand them a typical FPGA configuration cannot be read, only written.

So, sorry I do not think there will be hacking of the FPGA, not even by an expert like your Christer
(unless if I completely misunderstands FPGA's, not entirely impossible)


Also, it is unlikely the actual programming for any virtual CPU is in the flash. It is probably also in the FPGA.
Maybe a very small UI program (though I did not even see any strings, there was a high density section in the memory).

The reason I think so are these:
- The system starts up way too fast to download much software out of flash first
- The waveforms themselves (36+64@8192words) take up 1.6MB out of the 2MB. So not much left
- The actual signal processing at 2x250MSa/s does not allow for CPU based logic. Its all configured transistors.


BUT (http://www.st.com/content/ccc/resource/technical/document/application_note/b9/9b/16/3a/12/1e/40/0c/CD00167594.pdf/files/CD00167594.pdf/jcr:content/translations/en.CD00167594.pdf): At least we will be able to repair the broken waveform for that guy who lost his SINE. What that you or someone else?



EDIT: new info found (see other post for more info):

- Cyclone can self-read config, and its bitstream likely is in start of the windbond flash. So can be upgraded by us
- UI is in display SoC, still need to figure out how to read/write that.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Diabolo on November 18, 2017, 10:22:59 pm
Hello,

On the front panel there is, unless I am mistaken, 1 STM32F103C8.
What do you think ?

Diabolo
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on November 18, 2017, 10:25:03 pm
Hello,

On the front panel there is, unless I am mistaken, 1 STM32F103C8.
What do you think ?

Diabolo

... and its jtag is just under the connector to the main board. Should be capable of a dump.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 19, 2017, 01:56:14 am
Hmm, I did not even look at the display board. A bit short sighted of me.

I will look at that, out of interest, but I suspect the situation remains the same, its just a display driver.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on November 19, 2017, 02:09:51 am
Hmm, I did not even look at the display board. A bit short sighted of me.

I will look at that, out of interest, but I suspect the situation remains the same, its just a display driver.

There are a couple of issues with the display that could be fixed. For one thing, the font. Its gross and not the most legible. Another thing is the frequency display. Strip leading zeros, standardize units, more legible colours, etc. I'm sure there are other changes that people would want. If its only the display driver, maybe FeelTech could see their way to making it Open Source.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Mr. Scram on November 19, 2017, 02:28:11 am
There are a couple of issues with the display that could be fixed. For one thing, the font. Its gross and not the most legible. Another thing is the frequency display. Strip leading zeros, standardize units, more legible colours, etc. I'm sure there are other changes that people would want. If its only the display driver, maybe FeelTech could see their way to making it Open Source.
Yeah, that very typical font has to go. A lot of the cheap Chinese stuff comes with it and it's a shame to have it detract from the device. Mind you, I can imagine it's all the same to someone whose native alphabet is different.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on November 19, 2017, 08:54:04 am
BUT: At least we will be able to repair the broken waveform for that guy who lost his SINE. What that you or someone else?
In reply to Cybermaus : Yes, it's me ! The Sine memory waveform is a flat line on both channels.
And I guess that could help that guy too : https://www.eevblog.com/forum/repair/reflashing-or-resetting-a-feeltech-fy6600-signal-generator/ (https://www.eevblog.com/forum/repair/reflashing-or-resetting-a-feeltech-fy6600-signal-generator/)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 19, 2017, 09:52:00 am
well, get your own CH341A and read the flash, so we can compare and then repair.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 19, 2017, 09:54:14 am
Not sure if I can get as motivated about fonts as for the other stuff that was already done.

For new buyers and users, a summery of what can be done, with links.
(so no desires and rants but achieved items)

1: The power supply can be made less leaky
Simple solution is to add a grounded socket  (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1343235/#msg1343235)and either fully ground the device, or add some Y-caps (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1344167/#msg1344167) or reconnect the one already there (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1347131/#msg1347131)
Deep solution is to fully replace the supply (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1348087/#msg1348087)

2: The time base can be made more precise
Simple solution is to replace CXO with a 0.1ppm TCXO, (https://www.ebay.com/itm/263019239549) either directly 50Mhz or a a 10MHz one with a PLL multiplier (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1346454/#msg1346454)
Deep solution is to add a external GPSDO or OCXO or external 10MHz reference source (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1347624/#msg1347624)

3: Good waveform at lower Vpp, but at full 20Vpp and above 5MHz, it can be improved
Replace the end opamp with two separate better ones (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1348087/#msg1348087)
May also need a new power supply, with a little more oomph to keep the +-15V up, see 1: above

4: DC Offset and Vpp calibrations can be tuned.
Unfortunately not (yet) by firmware, but simply tweak the pots on the board. (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1351221/#msg1351221)


Did I miss anything? (something people can do, not things we would like to do)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Diabolo on November 19, 2017, 04:41:12 pm
Hello,

For the power supply with 15V, be careful the internal capacitors are maximum 16V !!

Diabolo
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: ArthurDent on November 19, 2017, 06:25:32 pm
Cybermaus has listed the modifications that have been tried and seem to work so you can pick and choose what ‘options’ you want to add to your FY6600 from the list.

I have chosen to carry the ground (earth) from the 3-wire cord I added through to the power supply output ground and to replace the wimpy original supply with a heftier one. I’m not convinced that anyone can guarantee that all the parts will continue working at +/-15V instead of the +/-12V the board calls for. The board appears to work just fine with the +/-15V but with the part numbers ground off some ICs I don’t think there is any guarantee that some of the mystery parts aren’t seeing a higher voltage than they are designed for so I’m going to stick with a replacement +/-12V supply. The one I had used originally was a 40W supply that was much larger than needed but I had it on hand. I found a good quality 25W +/-12V supply for $13 plus shipping that doesn’t waste as much power (2W less than the 40W supply) so I’m using that supply as shown in the photos. I did find an excellent +/-15V supply that will just physically fit if I decide later to go with the higher voltage and that supply cost me about $13 with shipping and I have a photo showing how that would fit in the FY6600.

The OCXO I added is working great and if I leave the rear switch on so the OCXO is always warmed up the 10Mhz seems to generally stay within +/-.005Hz (9,999,999.995Mhz to 10,000,000.005Mhz) and I have the switch and BNC I added to the back to connect an external 10Mhz standard if I want.

I should get the THS3095D chips to replace the output amplifier chips and I think that is the last (really!) modification I’ll make unless I go with the +/-15V supply at a later date.

+/-12V supply  http://www.mpja.com/ (http://www.mpja.com/) Stock No: 34322 PS
+/-15V supply Ebay # 263326410466
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on November 19, 2017, 06:56:11 pm
I'll definitely do the time base next as the TCXO and PLL only consume a few more mA than the current 50Mhz crystal so the original PSU is still OK. It would also be an opportunity to add an external port for the 10Mhz like you did. This should be standard on even low end wavegens. I'm going to wait for the 3491's to be released and examined before I go further as I'm not sure about running the rest of the board at 15V. I don't have much of a need for more than a few V's of output anyhow.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 19, 2017, 07:30:24 pm
I’m not convinced that anyone can guarantee that all the parts will continue working at +/-15V instead of the +/-12V the board calls for.

Remind me, why do we believe the board calls for +/-12V?

At first I also I also thought it was a common +5V +12V board because not only is that common, but also someone reported that. But that very same person also mentioned his 12V supply was not very good because it was almost 15V. And mine is also hovering between 14.5V and 15.2V.

So I am wondering, maybe it simply is supposed to be a 15V supply? After all, +-15V is not an uncommon rail for OpAmps. So indeed, remind me, why do we think it is a +/-12V board?

I do agree though, if 15V, make sure you do not creep toward 16V.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on November 19, 2017, 07:42:23 pm
I’m not convinced that anyone can guarantee that all the parts will continue working at +/-15V instead of the +/-12V the board calls for.

Remind me, why do we believe the board calls for +/-12V?

At first I also I also thought it was a common +5V +12V board because not only is that common, but also someone reported that. But that very same person also mentioned his 12V supply was not very good because it was almost 15V. And mine is also hovering between 14.5V and 15.2V.

So I am wondering, maybe it simply is supposed to be a 15V supply? After all, +-15V is not an uncommon rail for OpAmps. So indeed, remind me, why do we think it is a +/-12V board?

I do agree though, if 15V, make sure you do not creep toward 16V.

Its stamped +-12V on the board. Mine measures +15.8V and -15.2V unloaded.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: ArthurDent on November 19, 2017, 07:48:20 pm
Here's a photo of the voltages on the power supply board. The numbers are almost hidden by the connector.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on November 19, 2017, 07:49:55 pm
Somewhat unnerving that its labelled as 12v but measuring 15.8V and has 16V rated output caps. They should be 25V rated.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Diabolo on November 19, 2017, 07:54:18 pm
Hello,

Nobody tried the THS3092 which contains 2 AOP +/- of THS3091 in the same S0P8 case, or almost "equivalent" to 30021 of origin FY6600 ?
Datasheet THS3092 :
http://www.ti.com/lit/ds/symlink/ths3092.pdf (http://www.ti.com/lit/ds/symlink/ths3092.pdf)
----
Buy THS3092 :
https://fr.aliexpress.com/item/THS3092-THS3092D-THS3092DDA-THS3092DDAR-3092-SOP/32827398519.html?ws_ab_test=searchweb0_0,searchweb201602_3_10152_10065_10151_10344_10068_10345_10342_10343_10340_10341_10541_10562_10084_10083_10305_10304_10307_10306_10177_10302_10060_10155_10154_10539_10312_10059_10313_10314_10184_10534_10533_100031_10103_10073_10594_10557_10596_10595_10142_10107-10177,searchweb201603_14,ppcSwitch_4&btsid=fa0c137f-85cc-4348-92e5-524764005c20&algo_expid=d4b84c0c-c840-4c1c-99cd-e0f428d02b99-7&algo_pvid=d4b84c0c-c840-4c1c-99cd-e0f428d02b99&rmStoreLevelAB=0 (https://fr.aliexpress.com/item/THS3092-THS3092D-THS3092DDA-THS3092DDAR-3092-SOP/32827398519.html?ws_ab_test=searchweb0_0,searchweb201602_3_10152_10065_10151_10344_10068_10345_10342_10343_10340_10341_10541_10562_10084_10083_10305_10304_10307_10306_10177_10302_10060_10155_10154_10539_10312_10059_10313_10314_10184_10534_10533_100031_10103_10073_10594_10557_10596_10595_10142_10107-10177,searchweb201603_14,ppcSwitch_4&btsid=fa0c137f-85cc-4348-92e5-524764005c20&algo_expid=d4b84c0c-c840-4c1c-99cd-e0f428d02b99-7&algo_pvid=d4b84c0c-c840-4c1c-99cd-e0f428d02b99&rmStoreLevelAB=0)


Diabolo
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 19, 2017, 08:00:20 pm
+/-12V supply  http://www.mpja.com/ (http://www.mpja.com/) Stock No: 34322 PS
+/-15V supply Ebay # 263326410466

Ebay # 263326410466 : Does not ship to the NL
HUGE pity, because $6 seems a steal, even pre-owned.

Same on Mouser: End of Life: Scheduled for obsolescence. And a €93 price (on top of nl.mousers standard of € 20 shipping)
Makes the $6 seem like even more of a steal. Even when adding $8 shipping to US.

I am tempted to ask you to get me two of those boards, but I will not be in US till May, and not sure what privately international shipping would add to the cost. Why do so many US eBayers not ship international! (I did send him a message, but usually they answer they simply do not want the hassle)

Actually, this Meanwell is local and not a bad price:
http://www.meanwell.nl/products/Meanwell-PT-45C---PSU-pcb--plus-5V-5A---plus-15V-23A---15V-05A__PT-45C.aspx (http://www.meanwell.nl/products/Meanwell-PT-45C---PSU-pcb--plus-5V-5A---plus-15V-23A---15V-05A__PT-45C.aspx)
A bit oversized though, but it seems to be there smallest tripple output

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Vytautas on November 20, 2017, 01:37:28 pm
As a reply concerning the 3092. It could be a better option than the original "30021" also, though sharing the load between two chips instead of one is better, IMHO.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 20, 2017, 02:36:51 pm
Some more info on the firmware from the flashchip:

Waveforms:

By creating square waveform, uploading, and then rereading the flash, I found the following:

A waveform is 16K in size. Arb1 starts at 0x0100000 with 64 waves that means precisely the last 1M (iow, second half of the full 2MB chip) is filled with the 64 ARB waves of which the first 32 is a repeat of build in, and the last 32 are all xFFFF values. There is no meta-data at all. The little graph on the screen is calculated on the fly, and there is no descriptive string,.

Looking at the data, it is all xFF3F for +1 and x0000 for -1 of the defined square wave as defined in the tool.
So the data is in LSB, and should read x3FFF instead, which is exactly 14 bits.
x0000 is -1, what we consider 0Vdc is x2000 and +1 is x3FFF

I also possibly spotted an a few wave definition errors:

The wave generated and uploaded by the tool is 8191 words long, the space in the flash 8192 words long, and indeed there seems to be one leftover word with a odd value in the flash. This could give spikes on the waveform? Need to check.

The square wave generated by the tool starts with a single +0.5 value before staying on +1 half the way. I suspect it is because the tool average values and start with 0. In any case, this could explain the 7.4ns risetime I noticed on the official square wave, vs 4.8ns on all other vertical edges. It may be they generated the official one also with the tool.
Indeed, when I made my own square wave, it gave me a 4.8ns risetime. Pretty nice 31.250 MHz square (no jitter on 250MSa/31.250MHz)

Position 0x060000 to 0x0DFFFF are the build in waveforms, an exact copy of 0x100000 to 0x17FFFF, but not an exact match for the build in waves of the UI
I suspect that some of them, like Sine, Square, CMOS, DC are hardcoded FPGE procedural instead of numerical. Sine so it can go up higher, and Square and CMOS so you can control the duty cycle. And DC because I found no block of x2000 values.

Settings and Calibration:

By changing settings and then rereading the flash, I found the following:
Nothing changed in the Winbond flash. So there are no settings in the flash. None.
And I now believe also no calibration. Instead those are thus stored in the as yet unreadble STM32 chip on the UI board.

Cyclone Config:

I read some info on the Cyclone, and I now believe the first 0x05FFFF bytes are the Cyclone IV bitstream, which are read at startup. I added some references to the other post about flashing, including the official header description. So the flash is most of the firmware, it also has the FPGA stuff. But the display board SoC actually has the UI programming as well as all settings.

Memory map:

Unknown
0x000000 to 0x0000ff Mostly ff, some other values
0x000100 to 0x001341 Patterns many in dual byte pairs
0x001342 to 0x059d4f very low density data, mostly 0 bits
                     Maybe FPGA matrix pin connections?
                     Can FPGA self-program from flash? (answer: yes it can (https://www.altera.com/en_US/pdfs/literature/hb/cyclone-iv/cyiv-51008.pdf))
                     I am guessing. Not program or waveform data though
0x059d50 to 0x05ffff all ff. Filler to boundery


Build in waveforms in blocks of x4000
0x060000 to 0x0dffff (32 waveforms)

0x0e0000 to 0x0effff all ff
0x0f0000 to 0x0f0fff 16x a count from 00~ff (user or leftover development junk?)
0x0f1000 to 0x0fffff all ff

Waveform Arb1~64 in blocks of x4000
0x100000 to 0x17ffff repeat of x060000 to x0dffff
0x180000 to 0x1fffff all ff
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: ArthurDent on November 20, 2017, 04:28:24 pm
Cybermaus, check these Ebay listings for +/-15V power supplies as possible replacements for the +/-12V one in the FY6600. Both are small and should fit. I don’t know anything about the seller but their feedback is 100% and these supplies have worldwide shipping (~$20 to NL) so they might be worth checking. You first might want to measure what the minimum current drawn from each voltage rail is in your FY6600 is and check the specs on the power supply datasheet for each supply. I didn’t check the specs carefully so I may have missed something you’d find important. If both meets your needs I’d lean toward the RPT-60C model. Here are the Ebay listing numbers   252596788777  252511042883
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: chtech0710 on November 21, 2017, 05:05:43 pm
Hi,

i've got my FY6600 recently and now it has stopped working  :(

Because i've replaced the power supply, modified the housing and added some shielding, i can't send it back to the seller (or Feeltech anyways).
I don't think the new power supply has caused the problem, it's a really good one (actually the same that ArthurDent uses in one of his.)

I've measured all suppy rails (also on the voltage regulators), which seems fine.
I also read the Flash content and compared with the uploaded content from cybermaus (btw. THX for uploading  ;) ) and it's identically.
The next thing i've checked was the nStatus pin (pin 92, also available at R2) and the Conf-Done pin (pin 9, also available at R3) from the cyclone after power-on - if there is any error. Even all clocks are present and fine so the Cyclone seems to be okay.

But nothing happens on the front panel. Just 2 relay clicks after power-on. No display, no LEDs light up, no beep.

My guess is, the little STM32 is gone bad or it's memory became corrupted.
That would be most likely the case, because the FY6600 stopped working after a factory reset and power-off.

My question: is it possible to get the flash content from the STM32?
I would try to reflash it or replace the whole IC if i got the firmware.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 21, 2017, 06:25:57 pm
Sorry to hear that. Unfortunately you seem to be the 5th one where the device went bad.

It may be better to move your question to the other thread (https://www.eevblog.com/forum/repair/reflashing-or-resetting-a-feeltech-fy6600-signal-generator/) though, so we keep the flash corruption & problem emails in one place.

At the very least, read that thread, because it seems your failure mode is completely different then the other 4, who had all 4 had identical progressive problems, and yours is a sudden dead. So it may simply be a power problem on the display board.
Hopefully so, because I have a STLink2 flash/read tool underway, but it seems often these STM32 chips are read-protected in commercial products.

Also: So flashchip is completely identical. Ok. What version and frequency model?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: chtech0710 on November 21, 2017, 07:03:01 pm
Sorry, my fault. I just googled "FY6600 firmware" and as a result found this post.
Now i've read the other thread, but it doesn't help very much.

I don't think it's a power problem, because the 3.3V on the vreg for the STM are present and stable. (Perhaps, a transient killed the STM32? Mhmmm...)
I've tried to measure if the crystal (next to the STM32) is working, but nothing. I replaced it, nothing changed.

I've got the 30 MHz model. I think the version was the latest, i can't tell you exactly, cause i'm at home now and not at my workshop.

The content of the flash chip ist almost identically (havent checked every single bit  ::) )
I've read out the old firmware from the flash chip (and saved it). Have tried your uploaded one. Makes no difference if I try your firmware or the original one.
I do not think the Cyclone is broken. By capturing some data between the flash chip and the Cyclone, everything seems normal.

BTW, could a friendly moderator move my (and your last) post into the appropriate thread? THX  :)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Diabolo on November 21, 2017, 07:05:36 pm
Hello,

To read, write, remove read / write protection on STM32:
- http://www.jyetech.com/Support/STM32_FlashLoaderDemonstrator_v2.7.zip (http://www.jyetech.com/Support/STM32_FlashLoaderDemonstrator_v2.7.zip)

Diabolo
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: chtech0710 on November 21, 2017, 07:17:45 pm
Just recently used this tool to upgrade the firmware from my DSOShell, but I wouldn't have come up with the idea to use it for this problem.  ;D
But, this tool needs a bootloader to work? i dunno.

Anyhow, i will try it tomorrow. THX  :)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 21, 2017, 07:51:06 pm
From what I read in this STM32 doc (http://www.st.com/content/ccc/resource/technical/document/application_note/b9/9b/16/3a/12/1e/40/0c/CD00167594.pdf/files/CD00167594.pdf/jcr:content/translations/en.CD00167594.pdf) (yes, I have been reading a lot about the STM32 lately. Demo board and STLink2 tool should be here tomorrow), the bootloader is always present on this chips, in masked ROM even. Hence it can update using this serial tool.

But remember, you want to read, not write, the firmware.

But good to check the tool anyway, at least it will tell you if the chip is still alive.

Can you send me your WInbond flash file, so I can binary compare them?
ALso, I would really like to know what version your device was. Did you never look before it crashed?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: chtech0710 on November 21, 2017, 08:30:05 pm
Unfortunately, I do not have much experience with STM32 µCs. At work we use mostly ATmega, PIC, some lower-end FPGA or "fancy" embedded computers with linux. (it's a small company)

Good to know that the bootloader is always present. I will definitely try to unlock and/or read the content from the STM32 tomorrow (but only if the chip is alive  :-\)
And i will also upload the flash content from the Winbond flash ic.

Apart from that, by comparing available pictures of the hardware it almost looks like the hardware is pretty identical to most models (15/30/50/60?MHz). A comparison of the different firmwares should give us information about possibilities for hacks.  ;)

I was recently looking for an update of the firmware, but it was (and is) not possible yet, and unfortunately i didn't take much care about my fw version. I#m pretty sure it was the latest version 3.1(?)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 21, 2017, 08:55:44 pm
Careful with the "unlock". Not sure if you can do that from serial, but:

According to these people (https://www.usenix.org/system/files/conference/woot17/woot17-paper-obermaier.pdf), unlock from security level RDP1 to RDP0 is possible, but will auto-erase the flash, making the chip back ready for a new program, but not helpful for us.

They did find a way to read the flash while in RDP1, by means of a custom reader that resets the debug tool, it seems that each well timed reset leaks one byte of flash. But that will not work for normal available tools, and they did not release the software.

From what I understand, our only realistic hope is that the manufacturer did not secure the chip. Or makes the firmware available in order to stop negative posts.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: chtech0710 on November 22, 2017, 10:03:18 am
After many cups of coffee, and playing around i've managed to get access to the bootloader with the ST Flash Loader Demonstrator.

First of all, the memory is protected...  :'(
and by trying to unlock, it was auto-erased... damn!

In case someone else will try it:
USART1 isn't easy availlable, so you have to solder some small wires to the STM. The RX/TX from J1 are wired to USART2 and useless in our case.
First, we need to set the BOOT0 pin to high (3.3V) to enable the bootloader. BOOT0 is at pin 44.
USART1-TX is on pin 30 and USART-RX is on pin 31, which also goes to C1 and the encoder.
You have to remove C1, cause C1 acts like a filter. I've used the pad from C1 to attach the RX-wire.
We need the RESET-pin, which is availlable at pin 7 and R1.
GND and 3.3V are availlabe from JK1.

Finally, the baudrate is 115200,8N1 with even parity.
By using the Flash Loader Demonstrator, you shoud disable ECHO and set the timeout to 5.

And here are some pics showing my attempts to get access to the bootloader.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 22, 2017, 12:47:33 pm
Big bummer. No need for me to check anymore if the STM32 is locked

So there are already 5 people with broken STM32 flash. And we know how to write the flash.
We need some way to make the vendor relinquish the firmware?

Easy for me to say, mine is still working, but keep asking for service requests? Not buy anymore of their stuff until this is fixed / fixable.
That latter one is pretty understandable, as much as I am happy with mine, knowing it can corrupt its own flash at any moment means I would not recommend to others.


Sidenote, I checked your firmware file. While it appears the same on a quick glance, it is quite different.
Not only did you already upload the first and last few arbitrary waveforms, 2 of the build in ones are also slightly different.
And though not easy to spot due to the low bit density, the Cyclone part is also different all over.
So it seems they are making changes to the Cyclone between versions as well as the UI



Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on November 22, 2017, 10:19:07 pm
Disappointing about the firmware failures. Time for Feeltech to release a method and the firmware to fix this issue and enable user upgrading or repair.  :-+

This thread until it happens will continue to turn up very high in the search rankings and random failures that require unit returns to mainland China are not going to reflect well on sales.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Scratch.HTF on November 23, 2017, 02:42:49 am
Since I intend to sync this unit to an external frequency reference, is the frequency at the Sync OUT port 10 MHz?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Diabolo on November 23, 2017, 02:48:43 am
Hello,

Aie, it's a shame for the erased STM32 memory.
But we will find a solution to restore everything in condition. ;)
----
How does a power supply / charger for laptops, LCD TVs, GSM, etc ... (Sony, Asus, Samsung, etc ...) that have a 110V-220V with 2 pins compared to the ground?
They must also have 32V of differential with the ground under power supply AC 220V and the general mass ?
----
Datasheet on various TCXO, stability seems good for general purpose :
- http://www.metatech.com.hk/product/fordahl/pdf/2002%20TCXO%20Page%2043-58.pdf (http://www.metatech.com.hk/product/fordahl/pdf/2002%20TCXO%20Page%2043-58.pdf)
- http://docs-europe.electrocomponents.com/webdocs/0d5a/0900766b80d5a4cf.pdf (http://docs-europe.electrocomponents.com/webdocs/0d5a/0900766b80d5a4cf.pdf)


Diabolo
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 23, 2017, 05:39:23 am
Since I intend to sync this unit to an external frequency reference, is the frequency at the Sync OUT port 10 MHz?
No, but its fairly easily and effectively added. (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1346454/#msg1346454)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on November 23, 2017, 07:01:28 am
Hello,

How does a power supply / charger for laptops, LCD TVs, GSM, etc ... (Sony, Asus, Samsung, etc ...) that have a 110V-220V with 2 pins compared to the ground?
They must also have 32V of differential with the ground under power supply AC 220V and the general mass ?

Diabolo

Some are good some are junk  :--

Quick test on what I have on hand  on the bench at present 2-40V above ground. Includes built in USB mains adapters. 17V dc LED drivers. The one that is the best is also the cheapest  |O

I have a bunch of these all are in the 2V ac range  :-// https://www.ebay.com.au/itm/AC-DC-220-to-5V-12V-5V-600mA-Isolated-Switching-Power-Supply-Module-Power-Supply/400914188250?hash=item5d585907da:g:AYkAAOSwv0tVRd-R (https://www.ebay.com.au/itm/AC-DC-220-to-5V-12V-5V-600mA-Isolated-Switching-Power-Supply-Module-Power-Supply/400914188250?hash=item5d585907da:g:AYkAAOSwv0tVRd-R)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 23, 2017, 08:07:04 am
Test the illogically good cheap ones again while reversing their AC polarity.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on November 23, 2017, 08:49:38 am
Fairly humid and hot here tonight. To earth in bare feet on concrete I am generating about 200mVac  :o Also drinking my 3rd Beer and hot swapping 240AC what could go wrong  :palm:

column 1 is one way, 2 is reversed ac. First 4 including the 12V are the same manufacturer. Last 3 are just a few unearthed randoms LED drivers in the box, didn't bother reversing inputs need more :popcorn:

5Vdc 1 - 1.5Vac, 1.47Vac  5.0980Vdc
5Vdc 2 - 1.3Vac, 1.32Vac, 5.0860Vdc
5Vdc 3 - 1.46Vac, 1.45Vac, 5.084Vdc
12Vdc  - 1.14Vac, 1.13Vac, 11.992Vdc

3.16V ac 23.1Vdc
2.89V ac 20.9Vdc
75.1 Vac 12.1dc largest at 10Wand the most EXPENSIVE of the bunch  |O

So the conclusion from this is  :scared:
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: aylesj on November 23, 2017, 03:54:26 pm
If anyone was thinking of buying one, fasttech are offering 15% off everything at the moment (valid 23rd - 27th Nov), so the 60 MHz version can be had for $86.66 including delivery (Normally $101.95). Use the coupon code THANKS15 after you have added it to the basket.

Unfortunately I ordered one from them a week ago, so missed this discount. It took 8 days from ordering to receive an 'item shipped' email. I'm guessing it will take another 10-14 days to ship to the UK.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: plb on November 24, 2017, 12:07:24 am
Just received my FY6600. Free post, one week Shenzen to Sydney. Impressive.
This is my first post on this thread. I won't be hacking the instrument (much), but follow the thread with interest.

Not sure how to post a quote, but this from Cybermaus 3 weeks ago got my attention.
"So I took CH2, looped it into the VCO and that works but it is a bit unclean. In fact, I found it better to simply put a sawtooth on CH2 and do FM modulation, that also causes a frequency sweep. AM for amplitude sweep. For PWM, still have to use the CH2-VCO"
I find the Ch2 - VCO loop works well, but it is necessary to offset the Ch2 output otherwise you only get half a sweep. Ch2 swings around 0V, but VCO in expects 0-5V. Using CH2 with ramp in this way gives a trigger that is ideal for syncing the scope trace to the Feeltech.

Also I'm a bit intrigued by the power supply issue. As soon as I connect the Feeltech to a scope or other grounded instrument, its internal common is solidly grounded. Nevertheless I will be looking at a grounded IEC connector, as I do appreciate the risk of connecting the signal to a device under test before connecting the ground.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on November 24, 2017, 01:57:09 am
Welcome  :)

My main concern was frying a low voltage micro in some way with the high floating ground. My bench has a dedicated earth point if needed regardless but I really wanted it to remain floating depending on the application but with lower risk to any DUT.

More risk now of me frying the DUT than the Feeltech  |O
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 24, 2017, 07:10:29 am
Just received my FY6600. Free post, one week Shenzen to Sydney. Impressive.
I find the Ch2 - VCO loop works well, but it is necessary to offset the Ch2 output otherwise you only get half a sweep. Ch2 swings around 0V, but VCO in expects 0-5V. Using CH2 with ramp in this way gives a trigger that is ideal for syncing the scope trace to the Feeltech.

I have since created an dedicated ARB with a sawtooth from 0 to 1 rather then -1 to 1, but starting with a tiny -1 pulse to easily have the scope trigger.


Another usage tip I have since found (maybe common knowledge already)
People (including myself) complained both channels automatically start when you turn on the device. That is actually a setting in the system menu. (ChX boot Yes/No)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on November 24, 2017, 11:08:24 pm
I folks !

Finally I've decided not buying a new power supply, but making some modifications to the stock PS Feeltech.
I've focused my work on the caps and I would say that it's worth it.

The output filtering capacitors were swapped with low ESR and higher voltage ones.
Main front end circuit, a new high voltage cap 68µ/400v now takes place instead of the old crappy one (10µ/450v)
And last but not least, I've added a second HV cap between 0V and the unconnected mains.
It didn't cost me anything as I used parts from my old stock of electronic devices.


 
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on November 25, 2017, 06:14:18 am
I think your Power Supply board is now at 'capacity'  ;D

Did you run an earth wire or just the extra Caps to try and soak up a bit of the voltage?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on November 25, 2017, 10:11:39 pm
I think your Power Supply board is now at 'capacity'  ;D
Almost, but you know this PS is really a piece of sh..
I had to remove all the output diodes and replace them with more efficient ones. The gain is roughly +0,5V on each output.
Not so bad !

Quote
Did you run an earth wire or just the extra Caps to try and soak up a bit of the voltage?
Only an extra Cap so the leaked voltage is now half the value of the mains voltage.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: nctnico on November 25, 2017, 10:47:16 pm
It didn't cost me anything as I used parts from my old stock of electronic devices.
So replace brand new components with old ones in unknown condition?  :palm:
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Specmaster on November 26, 2017, 12:57:28 am
I folks !

Finally I've decided not buying a new power supply, but making some modifications to the stock PS Feeltech.
I've focused my work on the caps and I would say that it's worth it.

The output filtering capacitors were swapped with low ESR and higher voltage ones.
Main front end circuit, a new high voltage cap 68µ/400v now takes place instead of the old crappy one (10µ/450v)
And last but not least, I've added a second HV cap between 0V and the unconnected mains.
It didn't cost me anything as I used parts from my old stock of electronic devices.

Why is that transformer at that ridiculous angle, surely you sorted that out? :palm:
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on November 26, 2017, 08:23:05 am
So replace brand new components with old ones in unknown condition?
I never said that all my old stock is vintage, and I tested them before mounting on the PS pcb.
Reuse quality components for servicing is better than use brand new ones with low performances imho.

Quote
Why is that transformer at that ridiculous angle, surely you sorted that out?
Not at all, the FY6600 was delivered with the transformer in this position.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: bianchifan on November 26, 2017, 12:33:32 pm
2. Then, I replaced the dodgy output amplifier op-amp. The original one is an unknown 30021. At first I thought this is a dual variant of the single THS3001 but some guy has inquired about it from Texas Instruments and they replied that they do not manufacture such.
Your dodgy crappy unknown 30021 are very well known 3002I -> THS3002 with extended operational temperature!
They are used frequently in FeelTech Signal Genarators (esp. 32xx) and often discussed in russian forums like mysku, radiokot, x-faq and so on...
For various reasons many people prefer them to THS3092, although 3092 can drive more current.
(https://img.mysku-st.ru/uploads/images/04/34/11/2016/07/06/aa2276.jpg)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on November 26, 2017, 03:19:59 pm
Mine came yesterday.  Being forewarned I plugged it in and took a meter to it.  50 V between BNC and earth ground.  FeelTech *really* should fix that.  It's a huge menace to anyone using it as a signal source for embedded work.  I've generally steered clear of such kit because of this.  The *only* reason I felt comfortable buying one was the information from this thread.  Hopefully FeelTech will take that to heart and modify the design appropriately.   I'm mostly going to be using it with MCUs, so the other mods are less important to me.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 26, 2017, 04:29:31 pm
I really still believe it is theoratically inherent to the 2-prong class II design. In other words, all non-ground connected SMPS have it.
How much they have it depends on the size of the Y-Cap, and that depends on how much they want to suppress EMI and how much power supplies
(Note to self, I need to check that 'real good' Samsung USB for EMI leakage (but I do not have the equipment) and floating while loaded)

So I believe a design change simply means, factory fitted with 3-prong cable.
Which is a good idea, for sure.

Please note: I am not saying its a good supply, but in my view, the leakage is not part of its badness.
What is part of its badness is being labeled at 12V but giving over 15V, unconnected 20V but having only 16V caps.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on November 26, 2017, 04:40:59 pm
What is part of its badness is being labeled at 12V but giving over 15V, unconnected 20V but having only 16V caps.

Yes. This is not acceptable. The output caps should be 25V rated if the supply is giving 15V. The other problem is that the main board caps are all surface mount and 16V rated also. I'll have to probe around and see what the voltages are, especially around the output amplifiers.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on November 26, 2017, 05:52:08 pm
I just connected my scope to the ground of the unit.  Yikes!  Yeah, it's 50 Vrms, but it's 174 Vpk-pk!

The first scope image is with the probe connected to the BNC ground, no ground lead connected.  The second image is the BNC ground lead of the FeelTech connected to the scope ground via a 100K resistor and probe across the resistor.

It's so bad I'm reconsidering whether to keep it.  I notice that there are no approval marking of any kind.  It shipped from CA which raises the question of whether it's even legal to sell it in the US.

Edit:

Here's the drop across a 10K resistor.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 26, 2017, 05:56:25 pm
Now do the same for any other 2-prong device you have.
It will be better for smaller power supplies, but most of them look scary.

You are basically just measuring mains through a 1pF capacitor.

Whether you want to send back or not is up to you, but of you keep it, just do the 3-prong+y-cap mod.
I now have about 1Vac, and it is still floating. Or hard-link to the GND for 0V
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Specmaster on November 26, 2017, 06:01:22 pm
Quote
Why is that transformer at that ridiculous angle, surely you sorted that out?
Not at all, the FY6600 was delivered with the transformer in this position.
WTF is that all about then, is there something under it like thermal cutout or what, if there's nothing there then I would have certainly have corrected that, its a reasonable sized lump flapping in the breeze there and producing untold stresses on the PCB due to inherent vibrations.  :palm:
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on November 26, 2017, 07:14:37 pm
Now do the same for any other 2-prong device you have.
It will be better for smaller power supplies, but most of them look scary.

Interesting.  I just repeated the test with a 5V wall wart supply from a kit of Arduino stuff.  Very similar picture.  I'd never  considered the matter.  Good thing to be more aware of.  I'd never thought closely about ground loops in my bench setup, but clearly with a variety of power sources and grounds, it gets messy.

I'm looking it over closely.  I don't understand the main board SMD electrolytic markings.  Two are clearly marked 16 V, but most are marked "100 10S 3R7"  Has anyone got a decoder ring?

I shall certainly put a proper ground on it if I keep it.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 26, 2017, 07:35:31 pm
I'd never  considered the matter.

Same for me, till this thread. Learned a bit

I have a old ATX power supply that I use for easy and beefy +5V and +12V (as well as minor -12V)
I had isolated them from ground, yeaaaars ago, never had a problem.
Probably because I always hook up 0V first, and then my DUT is referenced to that 0V.

But just to feel happy, I just added a capacitor and 1 meg resistor to ground there too (I like to keep it floating)
Now also looks a lot nicer. from 60Vac floating to 1Vac floating


Basically, the build in Y-cap crossing the transformer has to be significant larger (10x) then the inherent capacitance of the transformer itself, to avoid EMI.
And to counter mid-point "leaky" ac voltage, the cap from secondary 0V to ground should be significant (10x) bigger then that Y-cap
I believe this 2nd cap does not need to be Y, I am using X. Because it is not connected to mains. Also because I have those.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on November 26, 2017, 07:52:21 pm
Now do the same for any other 2-prong device you have.
It will be better for smaller power supplies, but most of them look scary.

Interesting.  I just repeated the test with a 5V wall wart supply from a kit of Arduino stuff.  Very similar picture.  I'd never  considered the matter.  Good thing to be more aware of.  I'd never thought closely about ground loops in my bench setup, but clearly with a variety of power sources and grounds, it gets messy.

I'm looking it over closely.  I don't understand the main board SMD electrolytic markings.  Two are clearly marked 16 V, but most are marked "100 10S 3R7"  Has anyone got a decoder ring?

I shall certainly put a proper ground on it if I keep it.
The caps marked 10S are 10V. I checked continuity and none are connected to the "12"V rails. They are connected to the 5V or come after some of the other linear regulators on the board. The 16V ones do have continuity to the 12V rails. Hopefully they hold.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 26, 2017, 08:19:49 pm
The 16V ones do have continuity to the 12V rails. Hopefully they hold.

When I worked on the supply, and had it disconnected, I measured 20V.
Before I connected to the AWG board again, I had the presence of mind to first discharge the power supply caps. Gave a bit of a zap. Imagine hooking up the AWG board with 20V precharged into the caps...
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on November 26, 2017, 08:26:31 pm
My supply measured 15.8V when unloaded. Appears to be a lot of variability, at least when measured unloaded.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on November 27, 2017, 02:21:41 am
I worked up the nerve to connect it to my new scope.  The Instek spectrum analyzer demo allows the user to control the SA settings by pressing the lower right corner button  by the screen.  I've set it up for 0-100 MHz span.  As far as I can tell, this is the MDO line SA function.  It's a bit flaky, but seems pretty usable if you  can accept an RBW of 10KHz.  The white trace is a 16 point average of the spectrum.

The plots are 0.1 V, 1.0 V and 10 V output settings.  At low output voltages it looks quite good, but the harmonics get really bad above 1 V.  The obvious question is, is it the PS or the PA?

It seems to me the appropriate next step is to hook it up to my bench supply.

The SG is set to 5 MHz.  I'm using an MSO-2204EA.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on November 27, 2017, 02:43:49 am
For the sake of comparison here is the internal AWG on the Instek MSO-2204EA at 1 Vpk-pk and 5 V pk-pk.

Edit:

For completeness I've added the 0.1 V case.  The Instek built in AWG pretty much goes to hell around 1.5 V.  5 V is the max.

All the plots had a 6 dB attenuator inline to provide a 50 ohm match for the source.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 27, 2017, 06:18:05 am
That is undesirable. I do not have a SA myself (and my  rigol FFT is non-usable) but looking at this link (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1339656/#msg1339656) it should be much better.
Vpp is not mentioned, so I am assuming 5Vpp default.

Maybe your log steps of 0.1 - 1 - 10 are a bit too much, and the supply only falls short over 9Vpp
So mid-voltages are still good.

But this guy (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1348087/#msg1348087) does indeed claims both a better Op-Amp and a better supply are needed at 20Vpp.

Interested to see what it does when hooked to your bench supply instead of internal, but smaller steps please.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on November 27, 2017, 01:32:13 pm
The harmonics grow rapidly above about 1.5 V.  5 V was the limit on the Instek AWG.  I am unable to control the input attenuator in the SA demo.  So some of this may be sampling artifacts.  I'll repeat later today with the regular FFT function.  Unfortunately, that does not have the ability to super impose a running average of the spectrum.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on November 27, 2017, 10:41:06 pm
Here are screen shots with the generator running from an Instek linear bench supply feeding +- 12 & +5 V.  The harmonics start growing around 6-7 V.

For these I used the regular FFT function rather than the SA demo.  I think a lot of the harmonic distortion in the previous screen shots was the scope attenuator being set too low and clipping the ADC input.  The SA demo does not allow any adjustment of the input channel gain that I can tell.

There's a 6 dB attenuator inline to provide a 50 ohm termination to the FeelTech.

I'll repeat the same tests using the internal PS later.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on November 27, 2017, 11:19:32 pm
Here they are using the internal PS.  I can't see a significant difference toggling between the images.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 28, 2017, 05:57:26 am
Here they are using the internal PS.  I can't see a significant difference toggling between the images.

So if I read that correct:

+01Vpp -55dB
+05Vpp -55dB
+10Vpp -44dB
+15Vpp -31dB
+20Vpp -25dB

I actually think that is pretty good. That is still 25dB down at full 20Vpp swing....

I'd argue the old argument that it is only a $100 device, comparable features to a to a $900 Rigol DG1062Z
But to be quite honest, I think that Rigol may not fare much, if any, better at +20Vpp

For comparison, look at the remainder of this video (https://youtu.be/ML-lmuHoh-0?t=1792) on the previous generation of cheap awg.
If I can eyeball the distortion, imagine the spectrum on that?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on November 28, 2017, 01:47:14 pm
I think it is quite good, especially for the price. And with my embedded & SDR  focus I can't imagine a need to go above 5 V.  I've noticed that there is a relay click when going from 5 to 6 V.

For my purposes I think all that's needed is to suppress the AC leakage.  Which raises a question.  One Y cap or two?  I'd never even heard of them, but the last time I was heavily active in electronics (i.e. had a bench set up) most supplies were linear.

While fooling around last night I noticed some curious behavior for ARB28 when I varied the frequency setting.  So an investigation of the frequency axis seems in order for this evening.  Unfortunately, it appears that either the dual display FFT or the V 1.32 FW update removed the ability to display an FFT all the way to Nyquist which is rather annoying.  So I got a better UI at the price of reduced functionality.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on November 29, 2017, 01:19:25 am
Here is a plot of 1 MHz at 1 V.  Cursor measurements give the following:

2nd  -60
3rd   -64
4th  -60
5th  -60
6th  -52
7th  -62
8th  -60
9th  -60

Noise floor -72

The Instek SA demo is set up with the internal function generator a 1 V.  The input attenuator setting is unknown, however, I should expect that Instek made there demo look as good as possible.  So I think the results are reasonably accurate within the limitations of 8 bit sampling.  Looks quite good to me. In fact, amazing.  I don't want to think about what it would take to build an analog 1 MHz oscillator with equal performance.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on November 29, 2017, 02:17:53 am
Here are spectra at 1 V for 10-60 MHz in 10 MHz steps.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on November 29, 2017, 02:39:52 am
Same setup, but 1 MHz span
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 29, 2017, 07:11:49 am

I wonder if those sidebands (at roughly 30KHz / 300pSec offset) are jitter from the oscillator.

Would be interesting to see if they still exists after replacing that oscillator with that NB3N502 PLL that supposedly only has 15pSec jitter
Either ArthurDent needs to check that, or I need to buy a decent Spectrum Analyser.


Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on November 29, 2017, 03:31:06 pm
It appears to be a sampling artifact.  Here's what an RSP2 says set to 5 MHz BW.  10 MHz BW is similar.  The display is *very* different with narrower BW to the point of not seeing a pronounced peak at 40 MHz.  Not sure what is going on.

I've added a shot with the RSP2 set to 4 MHz BW.  Very strange.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on November 29, 2017, 09:26:49 pm
It appears to be a sampling artifact.  Here's what an RSP2 says set to 5 MHz BW.  10 MHz BW is similar.  The display is *very* different with narrower BW to the point of not seeing a pronounced peak at 40 MHz.  Not sure what is going on.

I've added a shot with the RSP2 set to 4 MHz BW.  Very strange.
Actually it isn't so strange at all, a SDR is not a spectrum analyser with professional specifications.
I think that relevant spectrum analysis can only be done with a spectrum analyser, and fortunately I own one.
I'll send full detailed spectrum traces to that thread in the next coming days if someone is interested in (no time for doing that right now)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on November 30, 2017, 04:07:24 am
Turns out the front end was being overdriven and went into oscillation when the bandwidth changed.  Not yet sure why it does that.

An SA is the next item on my shopping list, but good ones are expensive.  The RSP2 does a pretty good job over a 10 MHz span.  So combined with the FY-6600 it should be usable for checking filters for HF.

The sidebands displayed by the RSP2 are very different from the picture presented by the scope FFT.  For close in, I'm much more inclined to believe the RSP2 as the RBW is much smaller.  There's really not a lot of control of the FFT parameters on the scope and the dynamic range is also smaller.

For "no-signal" I just disconnected the AWG.  It seems likely that the RSP2 close in spectrum is the more accurate.

It would be very helpful to have spectra from a calibrated commercial SA to compare to the RSP2 and scope FFT plots.  I'm trying to sort out which of these things I should believe and when.  So references are very helpful.

I fitted a grounded plug to my FY-6600, but still need to get Y caps for it.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on November 30, 2017, 06:28:17 am
I fitted a grounded plug to my FY-6600, but still need to get Y caps for it.

In my view:

Y-cap are safety. Because mains to any touchable item *must* be safe, even when it fails, they must be super safe, tested to 10KV as well as (I presume) lots of mechanical stresses. That is why the capacitor spanning the transformer must be a Y-cap, as it is potentially violating the galvanic isolation.


But you are planning to put a cap between an already safe item (the BNC is already touchable safe) and earth (also already touchable)
So while the habit for these things is to talk about y-caps, other caps should also be OK. I did put a Y cap, because I had one, but on my other 2 supplies that I modified, I put X-caps (because I had only 1 Y-cap)

Also, as I wrote earlier, the mains-to-0V Y-cap should be significantly higher then the transformer parasitic capacitance
And the cap from 0V-to-earth should be significantly higher than that to divide up the floating mid-voltage to null potential as much as possible.

But it should not be too high. At least, not if you really want to use the signal gen as floating.
Because it does have "probe loading" consequences. If/When you connect the signal to a DUT that is not 0V potential, it will first have to charge the cap to whatever potential the DUT is. And you do not want that to be too much of a jolt.


So the original Y-Cap is about 1nF (I measured)
The extra Y-cap I used is 4.7nF (that was the only one I had)
I would try to not make it higher then 10nF


Of course, I am new to this particular topic, so do take my view with some critical thinking.


It would be very helpful to have spectra from a calibrated commercial SA to compare to the RSP2 and scope FFT plots.  I'm trying to sort out which of these things I should believe and when.  So references are very helpful.

I was also playing with SDR based SA. But I did not get any result that I would think usable. Nice to locate FM radio stations.
But as electronics SA: when you know what peaks to expect, you can find them. But only being able to find what you already know is there is of limited use. And I have to many other peaks that I suspect are artifacts, clouding up the picture.

Of course, my SDR is one of those toy DVB-RTL sticks that I had lying around. That RSP2 does look like it is giving better screens, but are they true?
If not, it may be better to not spend $150 for a RSP2, and put that toward a real SA instead?



Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on November 30, 2017, 06:40:57 am
Would like a SA but luckily I can 'borrow' some time on a nice HP if needed  8)

Toy Budget left this week -$500+ pushing four figures  :palm:
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on November 30, 2017, 02:33:10 pm
There are lots of spurs as there are in any radio,  SDR or analog.  I'm quite happy with the RSP2.  The software less so, but SDRuno seems to provide pretty usable displays.  Now that I have serviceable signal sources I think I'll start a thread on the RSP2 showing it's application to filter characterization, etc.

The thing that is needed most for using an SDR as an SA is the ability to store a reference trace and then divide by the reference trace.  That would allow correcting for internal self noise and source variations and is a standard feature on an SA. Hopefully someone with access to an SA and an FY-6600 will repeat my examples and post them.  I'm most interested in the "signal", "no-signal" example with the small RBW.  I'd really like to know if that's a proper result.  The software aspect of T&M kit makes me reluctant to trust anything very much.

The LimeSDRmini should be a good low cost, wide range SA-TG with appropriate packaging and software.  I've got a LimeSDR which I bought mostly for use as a test instrument.  Still working on suitable packaging.  They get hot and they need shielding.  The RTL and RSP are based on clever use of TV tuner chipsets.  There's a wave of much more general chips coming along which should provide substantially better performance.

Now that I've started using Windows, I'm considering a VNWA from SSDR-kits very seriously.  The support in the yahoo group is excellent.  For a long time I refused to use Windows, but I find Linux not all that much better and there is far more Windows EE software available.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on December 02, 2017, 01:41:22 pm
Hi folks
for those who are interested in some measures relatives to the HF behaviour of our beloved one, here it is.
SA is a Rohde & Schwarz, Professional reference in Spectrum analysis.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: technogeeky on December 03, 2017, 06:54:21 am
Hi folks
for those who are interested in some measures relatives to the HF behaviour of our beloved one, here it is.
SA is a Rohde & Schwarz, Professional reference in Spectrum analysis.

That's actually pretty damn impressive.

The two anomalies that I see are between picture 14 and picture 15 (why is there a 10dB rise in the noise floor, but only on the lower sideband?), and between pictures 16 and 17 (why would moving from 14.8 MHz to 14.9 MHz add some comb of spikes just above the noise floor?). I don't think either of these two things are deal breakers (after all, these two problems lie 70 dBc and 65 dBc down, respectively). But I would be curious to hear a hypothesis about them.


And just for reference, please edit the post to include the exact model of the specan and the R/S signal generator (not that I doubt their performance, but perhaps someone wants to get a sense of the instrument's noise floor and phase noise).


Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on December 03, 2017, 06:58:15 am
I also have the impression the source column in the table may be incorrect.
Or else I cannot explain 14,15 and 16,17, why measure the same thing twice on the same device?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: technogeeky on December 03, 2017, 09:13:23 am
I also have the impression the source column in the table may be incorrect.
Or else I cannot explain 14,15 and 16,17, why measure the same thing twice on the same device?

It's not the same. I think he must have noticed that a small difference in frequency (10.7M vs 10.8M, and 14.8M vs 14.9M) causes marked differences in output.

The center frequency is the same, but the actual main tone can be seen shifting in both cases.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on December 03, 2017, 10:09:31 am
It's not the same. I think he must have noticed that a small difference in frequency (10.7M vs 10.8M, and 14.8M vs 14.9M) causes marked differences in output.
The center frequency is the same, but the actual main tone can be seen shifting in both cases.
Yes, that was my point, focusing on figures at particular frequencies.
For instance 10,7MHz, at this specific frequency, the noise floor raise suddenly 10db on the lower frequencies, really strange behaviour indeed.

The test equipments that I use are :
SMG = 801.0001.52 Rohde Schwarz signal generator 0.1-1000MHz
SA = FSC 3 Rohde Schwartz spectrum analyser 9k-3GHz
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: hainjedaf on December 03, 2017, 04:06:42 pm
Maybe a dub question, but I hope to learn:

I have a switchmode PSU (MeanWell PT-45B) kicking around. Would this be an improvement to replace the FY6600 psu?
Of course I'd add a grounded mains connector.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on December 03, 2017, 06:29:42 pm
In my view: Yes, but No.

Its too big, physically. Its also a bit of a waste, because its unneededly big, electrically.

It will also not get you any better leakage result then simply adding a 3-prong and connecting to ground:
Note the specifications of that supply (http://meanwellusa.com/productPdf.aspx?i=660#1) give you <0.5mA (or <500uA) leakage current, a lot worse than what is already in the FY6600. This is because the leakage is a function of the power a supply can deliver and as already stated the Meanwell is unneededly big.

It would really only improve the fact that the unknown Chinese PSU may blow its caps sooner rather then later and take the AWG with it.
Which is a big deal I suspect,

So while I am as yet choosing to keep the original supply, I cannot state that is a good idea. But that Meanwell is not a good choice.
Go with a smaller one. Or replace the 16 caps with 25V ones and add a 3-prong.





Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: hainjedaf on December 03, 2017, 07:48:25 pm
So updating the caps in the original PSU would serve better purpose.

Where does one hook up the PE lead? Secondary ground?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: don.r on December 03, 2017, 07:53:37 pm
So updating the caps in the original PSU would serve better purpose.

Where does one hook up the PE lead? Secondary ground?

That would be the easiest. The 25V caps don't fit in neatly as space is tight on the output side but they can be mounted a little off the board. Grounding should be on the secondary side, there is an empty pair of ground pads near the PSU output jumper that can be soldered to.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: xzswq21 on December 03, 2017, 09:03:10 pm

I wonder if those sidebands (at roughly 30KHz / 300pSec offset) are jitter from the oscillator.

Would be interesting to see if they still exists after replacing that oscillator with that NB3N502 PLL that supposedly only has 15pSec jitter
Either ArthurDent needs to check that, or I need to buy a decent Spectrum Analyser.

15ps is high :)
with 15ps of jitter and ideal analog output driver, we have:
@4.2MHz the ENOB<11Bits
@8.5MHz the ENOB<10Bits   ------>    SINAD<62
@15MHz the ENOB<9Bits      ------>     SINAD<60
@34MHz the ENOB<8Bits
@69MHz the ENOB<7Bits      ------>    SINAD<44
any bad layout, power supply noise, bad selection op-amp,... will ruin the performance.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: ArthurDent on December 06, 2017, 05:14:13 am
The array of modifications various posters have come up with to improve the FY6600 is interesting and depends a lot on what that particular user’s main requirements are. My first interest was mainly to make the FY6600 safer by including a real ground through a 3-wire power cord and not to rely on an iffy virtual ground.  Secondly I really wanted to make the timebase more stable and a LOT more accurate with the option of using an external 10 Mhz reference from GPS or a rubidium source. Along the way I discovered the existing power supply was crappy and not what I considered fixable so that had to be replaced as well. The grounding and timebase modifications I made worked as well as I hoped they would so that left the power supply and possibly the output amp that others considered lacking.

Recently I tried replacing the output amps as others had recommended and didn’t see that really improved anything for me and went back to the original single chip. I rarely go above 5 volts output so this modification wasn’t that high on my to-do list. Others have run the FY6600 main board on +/-15 to improve the output at higher levels with no reported problems but I was still worried about a possible failure. I had tried a +/-15 vdc supply I modified to put out about 14.2 vdc to perhaps give me a little more margin of safety. I was uneasy in running the main board at a full 15 volts with the caps on the board rated at 16 volts (as others have mentioned) plus I wasn’t so sure that some of the other parts wouldn’t be stressed by the higher voltage. Almost all SMPSs have one adjustment for the +5 and the other two supplies are ratios of that so to just use that adjustment to lower the +/-15 supplies to about 14.2 volts, which I thought might be safer, would mean that the +5 would be lowered as well by about .3 volts, and I didn’t find this acceptable. What I tried was to put a conventional 3-amp diode in series with the two + and – supplies which would drop those voltages by about .8 to .9 volts while leaving the +5 right on.

While that worked to lower the +/- voltages a little and made me feel a little better, the supply I used that just fit in the space in the case was a supply capable of supplying 60 watts. This meant that although the main board doesn’t require much power, the supply used 10 watts and most of that was given up as heat and the FY6600 ran warmer than I liked. The first 40 watt +/-12 vdc supply I tried was a little more efficient but still generated some heat and used about 8 watts. The supply I settled on was a 25 watt +/-12 vdc supply I have shown previously that uses only 6 watts when powering the FY6600 and 4-5 watts when the front switch is turned off but parts of the main board are still powered. Keep in mind that the OCXO that I used as a timebase stays powered when the back switch is on and does use about 1.5-1.8 watts when it is at temperature but that doesn’t contribute much internal heat.
 
Here are 2 photos. One shows how I added the diodes in series with the +/- supply lines and bypassed then with a couple of tantalum capacitors if anyone might want to try that. The second photo is of the 25 watt supply I showed before. I’m pretty sure these are all the modifications I’ll be making to the FY6600 but I’ll keep reading to see what other great ideas others come up with. In a way I spent more time with the FY6600 apart than with it together and doing what amounts to trying to make a Ford run like a Mercedes when I might have been better off buying the Mercedes in the first place! 
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: ArthurDent on December 06, 2017, 05:42:11 am
Oh, and one thing I've wondered about and it might be worth checking into, is the failure rate on the FY6600. One reason a lot of people are concerned about the leakage voltage on the output is that it could zap whatever you're connecting the FY6600 to. Is it possible that if you have an ungrounded FY6600 that you could zap it by touching the keypad? Capacitive coupling of the leakage voltage through the keypad could possibly account for this. Maybe there should be a poll of those who have had failures, especially of the display being garbled, to see if there is a correlation between ungrounded units and number of failures, or if it's just random.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on December 06, 2017, 05:57:32 am
Happy enough with mine with Earthing and extra Cap. Tweaks to the OpAmps were also well worth the effort IMO.

Disappointing that Feeltech haven't jumped back in to help out. The 'send it back to the factory' isn't adequate at this price point or day and age of 'easy' online firmware upgrades for plenty of other equipment.

If they chose to open source the firmware even and open themselves up to hackers and modders might see a boon in their sales numbers and be able to pick and choose mods by users to keep in the official firmware at little cost to themselves.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on December 07, 2017, 03:49:14 am
After I finished adding a ground and reassembled the unit, I ran it on the bench for an hour or so measuring the frequency with a counter and looking at the amplitude fall off at slightly over 50 MHz.  I put it aside (very cramped work space).  After supper I hooked it up to a scope to do some more analysis.  Borked display!

It works, but the display and UI are buggered, *exactly* the same as shown in the start of the thread on reflashing.  So it's obviously a pretty consistent defect.  I'm not clear on how cybermaus read the flash.  I chased some links, but didn't get anywhere.  I'll do some detailed testing to see if all the functions still work.

In looking at it, I notice that several chips next to the FPGA  have had the markings sanded off.  Has anyone else seen that?

Ironically, I had just given it a very positive review on eBay shortly before discovering it had borked itself.

 JK1 on the front panel board is the STM32 programming interface.  I just checked the pinout on the datasheet. Looks to be Spy-by-Wire.  I'll have to look at my collection of STMF32 boards to see if I can use one of them as a programmer/debugger.

There's been enough work done evaluating the unit, that I hope FeelTech will realize that they need to fix the bug and support the EEVblog community.  If it were reliable, it would easily be a very popular AWG.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on December 07, 2017, 04:29:17 am
All the waveforms seem to work except  SQUR, ADJ-PULSE and ARB33-64.  DC offset works. The other UI options seem a bit confused, but mostly seem to work.  A bit hard to test as I haven't had the unit long enough to get acquainted.

It is actually producing  NegRamp at the weird frequency that appears on the display at power up and the Vpp shown!
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on December 07, 2017, 05:30:12 am
Damn. another one.

As to how I read the flash: I read the wrong flash.
Since my original happy post, we learned that I read the FPGA and waveform flash, but the GUI and control flash is in the STM32 and that is the one that fails. Which alas is protected from reading. So we are at a dead end there.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: jleg on December 07, 2017, 10:46:57 am
All the waveforms seem to work except  SQUR, ADJ-PULSE and ARB33-64.  DC offset works. The other UI options seem a bit confused, but mostly seem to work.  A bit hard to test as I haven't had the unit long enough to get acquainted.

at this very similar stage i did a "factory reset" (load factory defaults from system menu) - after that, also the last working wave forms vanished...

The interesting question is: what firmware version does your FY6600 have? The current "hypothesis" is, that it is propably a bug of V3.0 specifically..
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on December 07, 2017, 02:17:34 pm
Mine is version 3.0.  Thanks for the warning about doing a factory reset.

I think it's time to sniff the cables from the front panel.  Has anyone checked the USB - PC connection?

Based on Ebel0410's spectrum analyzer plots, the signal generation board is very good.  So finding an alternative UI is well worth while.

As FeelTech is t least aware of this thread I hope they're paying attention and will respond appropriately.  There is certainly nothing in the UI worth protecting.

I still want to know how cybermaus read the flash.  I was already aware it was just the signal generator flash, but not the details of how.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on December 07, 2017, 02:33:30 pm
I did not sniff the USB connection, no, but I am not expecting anything of note in there, just the sending of control commands, but no way to read the flash.
Saying that out loud, I realize you may still be able to fully control the device, maybe even re-upload waveforms, using the PC program. But that is speculation.

I (and one other person) did hook up the STLINK to the STM32, and the flash is read protected, and unreadable, unless if you are a university level hacker (https://www.usenix.org/system/files/conference/woot17/woot17-paper-obermaier.pdf).

As to how exactly I read the FPGA and waveform flash: Please study this post and its video (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1352448/#msg1352448), and if that is not enough, please at least have specific questions about what steps you have trouble with. There is also a follow up post on the flash data structure.

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: jleg on December 07, 2017, 02:36:42 pm
Mine is version 3.0.  Thanks for the warning about doing a factory reset.

...looks like we now have 3 confirmed failures of this type, all with FW V3.0.

Afaik, current version is 3.2, so perhaps it is safe to try again and order a new one?  Hmmm... ::)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on December 07, 2017, 02:56:13 pm
 I would suggest no, because you should not reward this behavior?

If anything, you should nag them about warranty and refund, and if they go the "return at own expense" route, nag further about either the expense, or about at least sending out a pre-programmed STM32 for self-repair.

(Easy for me to say, I know, mine is still working. I am not sure I would could bring up to invest time in such a thing)

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: ArthurDent on December 07, 2017, 03:57:37 pm
I just checked the revision on my FY6600. It is V3.1 and it is still working properly. If the problem is only associated with V3.0 and newer/older versions are ok then I would think FeelTech would be obliged to offer those owners with V3.0 an free upgrade because they didn't get a properly working FY6600 that they paid for.

Some years ago I worked for a company that made a test instrument that had firmware burn into an eprom. Our customers were spread all over the U.S. and a very few scattered customers reported a strange intermittent problem. Seeing these instruments were used for billing huge dollar amounts this was a big deal.  Two of the instruments were sent back and I spent days trying and not being able to duplicate the problem until finally I saw the problem. It took some time to figure out what steps I had done to get the problem to appear because I had pushed a lot of buttons in multiple random steps to get there but I finally remembered enough of what I’d done to duplicate the problem repeatedly. What happened was that one data field had a fixed length and if you entered about 10 unique and not that common steps that data field length was exceeded, pushing data into the next field and someone would be billed many times what they should be.

It could be that in trying to improve the way the FY6600 worked in one area FeelTech inadvertently screwed up something else. It doesn’t seem likely that this could be a hardware problem from what you’re saying about V3.0 so it’s time for FeelTech to do something about offering a solution.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on December 07, 2017, 04:18:46 pm
I reread everything, watched the video and looked at all the pictures.  As I don't have one of those CH346s I was going to use a different device.

So to summarize:

The unpopulated header, S1,  next to the FPGA was what was used to access the Winbond  flash.

The PC software can't talk to the device properly even though I can still partially control it via the front panel.  However, it is less than stellar software, so a check by someone with a different FW version would be good.

I was referring to sniffing  the 8 bit bus from the front panel to the AWG board.  That's key to writing new UI firmware.  That should be a pretty simple command protocol.  So it should not be hard to reverse engineer.

There is also an XON/XOFF RS232 port coming from the UI board.

FWIW I read the Fraunhofer paper some time ago, so that has been in the back of my mind all along.

I'm going to raise the repair question with FeelTech to see if they consider the warranty void because of the ground modification.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on December 07, 2017, 04:27:01 pm
I would not even mention the ground modification, unless if they specifically ask about it.
If they do ask about it, it means they do read this thread, and are aware. Maybe no legal weight, but definitely moral weight into the matter.

They will try and evade the warranty by claiming you need to pay for return.
So my advised argument would be they are responsible for that. If they want to fix it, send out new device, front PCB, or maybe even only the STM32


but as mentioned, easy talk for me, I do not need to invest the time and effort.


Edit: the PC software does work for me to control the device. Pretty well even.

Edit2: Not that I think they will offer it, but anyway: Only accept a preprogrammed STM32 as solution if you have confidence in your own ability to solder it.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: feeltech on December 09, 2017, 12:56:09 am
The array of modifications various posters have come up with to improve the FY6600 is interesting and depends a lot on what that particular user’s main requirements are. My first interest was mainly to make the FY6600 safer by including a real ground through a 3-wire power cord and not to rely on an iffy virtual ground.  Secondly I really wanted to make the timebase more stable and a LOT more accurate with the option of using an external 10 Mhz reference from GPS or a rubidium source. Along the way I discovered the existing power supply was crappy and not what I considered fixable so that had to be replaced as well. The grounding and timebase modifications I made worked as well as I hoped they would so that left the power supply and possibly the output amp that others considered lacking.

Recently I tried replacing the output amps as others had recommended and didn’t see that really improved anything for me and went back to the original single chip. I rarely go above 5 volts output so this modification wasn’t that high on my to-do list. Others have run the FY6600 main board on +/-15 to improve the output at higher levels with no reported problems but I was still worried about a possible failure. I had tried a +/-15 vdc supply I modified to put out about 14.2 vdc to perhaps give me a little more margin of safety. I was uneasy in running the main board at a full 15 volts with the caps on the board rated at 16 volts (as others have mentioned) plus I wasn’t so sure that some of the other parts wouldn’t be stressed by the higher voltage. Almost all SMPSs have one adjustment for the +5 and the other two supplies are ratios of that so to just use that adjustment to lower the +/-15 supplies to about 14.2 volts, which I thought might be safer, would mean that the +5 would be lowered as well by about .3 volts, and I didn’t find this acceptable. What I tried was to put a conventional 3-amp diode in series with the two + and – supplies which would drop those voltages by about .8 to .9 volts while leaving the +5 right on.

While that worked to lower the +/- voltages a little and made me feel a little better, the supply I used that just fit in the space in the case was a supply capable of supplying 60 watts. This meant that although the main board doesn’t require much power, the supply used 10 watts and most of that was given up as heat and the FY6600 ran warmer than I liked. The first 40 watt +/-12 vdc supply I tried was a little more efficient but still generated some heat and used about 8 watts. The supply I settled on was a 25 watt +/-12 vdc supply I have shown previously that uses only 6 watts when powering the FY6600 and 4-5 watts when the front switch is turned off but parts of the main board are still powered. Keep in mind that the OCXO that I used as a timebase stays powered when the back switch is on and does use about 1.5-1.8 watts when it is at temperature but that doesn’t contribute much internal heat.
 
Here are 2 photos. One shows how I added the diodes in series with the +/- supply lines and bypassed then with a couple of tantalum capacitors if anyone might want to try that. The second photo is of the 25 watt supply I showed before. I’m pretty sure these are all the modifications I’ll be making to the FY6600 but I’ll keep reading to see what other great ideas others come up with. In a way I spent more time with the FY6600 apart than with it together and doing what amounts to trying to make a Ford run like a Mercedes when I might have been better off buying the Mercedes in the first place!


Thanks for using our products, we will replace the three-core plug in the next version to improve the stability.
If you have better comments or suggestions can be sent directly to the mailbox: admin@feeltech.net
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on December 09, 2017, 02:31:01 am
I sent FeelTech an email about my scrambled V 3.0 unit earlier today.  In it I linked both this thread and the reflashing thread.  I also explained about the grounding mod I'd done and why.  I saw the response in the reflashing thread even before I read the email response sent to me. That's *real* customer responce!

I've contacted the eBay seller about getting a new front panel so I can avoid redoing the power plug mod.  I added 200 nF from the PS ground to the plug ground which lowered the voltage on the BNC ground from 176 Vpp to 1 Vpp.  More work than I expected, but worthwhile.  The fiddle was because I had to add a small metal brace to support the plug receptacle I scavenged from a dead PC PS.

I rather hope they'll offer a revised unit with external reference input and a sweep ramp output.  I'll be very happy to buy another one with those features.  It makes them very handy for checking HF filters, etc.  You *can* do that by triggering on the width of the first sync pulse, but it's more fiddly than just using XY mode.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on December 09, 2017, 06:47:19 am
Amazing responses both threads.  :-+ Please keep us updated on how this warranty repair stuff works out.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on December 09, 2017, 05:30:50 pm
I sent "admin" a link specifically to Ebel0410's spectrum analysis post. That's pretty powerful marketing material for FeelTech. I've also noticed that there is another clone called Koolertron.  The other ones have nicer cosmetics, but lack the back panel options.  FeelTech has a number of variants, some in aluminum cases, but lacking the back panel connections.

The timing of ArthurDent's summary was quite fortuitous and feeltech's quoting it very encouraging. 

It would be very interesting to know who the designers are.  I noticed last night that Hantek offers design services both initial and updates.  It's entirely possible that the instrument section of FeelTech is a couple of people working in an LCD manufacturing plant who got funding to buy a design and market it.  If you think about it, the reluctance to provide schematics and source code may be contractually required by a design house when a manufacturer licenses a base design.  It would be interesting to hear from blueskull or some other Chinese member familiar with electronics manufacturing in China.  The "cloning" might not represent IP theft, but rather reflect product design as a service.  I can easily see a small manufacturer with excess capacity buying the rights to use a variant of an existing design rather than engineering there own product.

The seller, sportsgogo, replied saying they were contacting the supplier about my request for a new front panel.  I spent a long time last night browsing the sportsgogo eBay store "industrial" section.  Staggering assortment of goods. They have warehousing in the US, so if they will allow returns to the US rather than China I may shop there a good bit more.  I don't like buying expensive stuff direct from China because of the cost of a return.  But I'd be much more comfortable with shipment from China if I could make a return to a US location.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: bitseeker on December 10, 2017, 02:54:37 am
It would be very interesting to know who the designers are.

I agree that it'd be great to know more about the designer(s) of the FeelTech equipment. I had heard that they used to work for or have been otherwise associated with one of the competing companies in the space. Unfortunately, I don't have anything more concrete than that.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on December 11, 2017, 05:43:30 am
Slow day in the shack today. Such as the frequency measurement on the 34401a is. Very consistant with 30 minutes to an hour at each stop. Bit of flicker at 1Meg but most likely the agilent.

I have a couple of aged Polytron ocxo on the way to play with and make a 10Mhz standard not that I need better than it is  8)

Currently running 10.00042 Hz
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 12, 2017, 08:07:36 pm
As you may have seen in the other thread I've decided to spend some time reversing/redoing their FP software and got me one of the devices from a supplier that claims it's in Germany.
Before it arrives, cybermaus, did you hook the debugger and read the protection level, is it one or two ?
The panel controller is confirmed STM32F103C8 ?

  Best regards,
  DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on December 13, 2017, 03:30:07 am
Its one.

Though it is always possible they changed it to two on later builds / firmware's especially with all these links to Frauenhofer around.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 13, 2017, 07:06:50 am
Cool, that's nice to know, I'm curious what will be the level on mine, but as I've said, if we can recover the firmware it's perfect, to allow for a fast "clean room" implementation, similar with the Compaq and original PC BIOS, to get rid of all the copyright crap, if not, reversing the FP schematic and communication protocol with the signal board is the way to go, there are TONS of libraries for LCD driving and key matrix reading, hey we could even implement a FW update using either the USB or the, now useless, serial port header on the PCB.

Also, if its the level 2 already programmed, I've asked a more HW oriented friend what can we do, besides un-soldering the chip, and his response was disconnecting the power supply, and replacing it with a pulsing slightly negative current supply, something like 1KHz /-0.6V/few mA just to put the protection diodes in conduction, but not overload them, and then blasting the chip with a cooling spray to at least -25C or lower.
2-3 cycles and the flash content is gone, or so he says.
If I'll have to replace the chip anyway (if level 2 protection is programmed) I may try this before replacing the chip.

Related, if someone who had the generator FP borked, and can sell or loan the defective device/FP for a reasonable price, including shipping to Germany, for research purposes, please PM me. In case of a loan I promise to follow the pharmacists principle "Primum non nocere, hic curare" so it will most likely not have its state worsened.
 

Its one.

Though it is always possible they changed it to two on later builds / firmware's especially with all these links to Frauenhofer around.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Marco on December 15, 2017, 01:25:28 pm
Screw cleanroom, just throw the ripped flash on a torrent and publish improvements as binary patches.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Chris56000 on December 16, 2017, 07:40:51 pm
Hi!

My plan to buy one to document on this Forum has borne fruit and I'm expecting delivery after the Christmas Holidays!

I'll be posting pictures, details of FW version, waveform samples, plus circuit-details, parts lists, etc., rev'd from the unit exactly from as I receive it, and I'll report the effect of the OEM's "Factory Reset" - if it borks the unit then I'll send the STM32 FP Assembly to Member DC1MC for his perusal!

Unfortunately I haven't got (can't afford yet!) one of those nice colour-screen LED Oscilloscopes that other members publish their oscillograms from, I can only offer ordinary analogue 'scope trace pics for now!

Chris WIlliams
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 16, 2017, 11:34:09 pm
Hi Chris, thanks for the offer, it's gladly accepted, but let's hope that yours and mine won't do any borking at all and we'll do all the research just for the purpose of opening the firmware and extending the functionality.
Mine hopefully will arrive some time before Christmas so I can profit of the little vacation.
Don't worry about the scope, the time for it will come, but most likely you'll need some cheap Logic Analyzer because I'd say that the first thing is to sniff and decode the protocol between the FP and the signal board. Once this is done then the signal board could be controlled form other sources as well, I'll eventually produce a remote control device using the 7,99EUR OrangePi Zero that is a neat Linux system and much easier to program for non-trivial stuff than an Arduino (IMHO),.


Hi!

My plan to buy one to document on this Forum has borne fruit and I'm expecting delivery after the Christmas Holidays!

I'll be posting pictures, details of FW version, waveform samples, plus circuit-details, parts lists, etc., rev'd from the unit exactly from as I receive it, and I'll report the effect of the OEM's "Factory Reset" - if it borks the unit then I'll send the STM32 FP Assembly to Member DC1MC for his perusal!

Unfortunately I haven't got (can't afford yet!) one of those nice colour-screen LED Oscilloscopes that other members publish their oscillograms from, I can only offer ordinary analogue 'scope trace pics for now!

Chris WIlliams

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: ArthurDent on December 18, 2017, 09:57:59 pm
 I don’t have a real spectrum analyzer but I get a fairly good idea of how much jitter my FY6600 output has by observing the waveform on my scope at the highest sweep rate and lowest volts/division and also plotting the output frequency over time using a computer program. This plot also gives me a good presentation of how the OCXO I installed in the FY6600 drifts during warm-up after it has been off for a few days. I set the output to 3 volt and a sinewave of 10,000,000 Hz and then plotted this output compared to a modified Trimble Thunderbolt GPSDO and Lady Heather software so I’m not just checking the oscillator output against GPS but checking the output of the FY6600 after it has done all its magic to produce this frequency and waveform from the OCXO. There is always a retrace error with crystal oscillators so on every power-up they never settle on exactly the same frequency but are very close. On this test the 10,000,000.000 Hz output settled at about 0.047 Hz higher than the 10,000,000 Hz I set the OCXO to the last time I used it. This is why on frequency standard OCXOs once they have stabilized and have been adjusted you leave them on.   

Initially at turn on the output was high (low on the graph) but within 10 minutes it was almost at the exact frequency. For the next 20 hours the frequency increased about an additional .04 Hz before leveling off at about .047 Hz high. As long as the switch on the back is on the OCXO and parts of the main board have power but the display is blank. Because the internal timebase is close enough for most testing I would use it for I have found that leaving the switch on the rear panel off and having this small error isn’t a problem. If I need a really accurate frequency I have the added switch on the rear to switch from the internal timebase to one of my external standards which is always on and far more accurate and stable.  Even though the frequency of the FY6600 can be set in steps as low as microhertz I can’t see how I could use such small steps.

The attached photo shows the 10 Mhz output (in white) plotted over an almost 30 hour period. The first 20 hours the OCXO is warming up and settling at what will be its frequency for this power-up cycle. After about 20 hours the frequency is very stable but plotted over days and weeks you would see a smaller drift due to aging of the crystal. You can also see a slight temperature correlation after the 20 hour mark. Weight loss as atoms are ‘boiled’ off the crystal slab increasing the frequency slightly. The big dip in temperature (yellow graph) was cause by my house temperature being set lower at night.   
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on December 18, 2017, 10:55:46 pm
Talk about turning a Ford into a Mercedes!

Very cool.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 19, 2017, 05:42:08 am
Second this, transforming the device from a "meh-OK" device to an "almost R&S generator quality" is an impressive feat.

I hope that I'll be able to duplicate or come close o it on my device.

 Congraturlations Arthur  :-+
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 19, 2017, 06:18:20 am
Which replacement power inlet socket do you recommend ?

I like a lot these IEC320-C6 sockets, because the cables are less bulky then the usual ones:
https://www.mouser.de/productdetail/schurter/43000100?qs=sGAEpiMZZMv1TUPJeFpwblxZ%252bgbqW48rSymwXXVJLLw%3D (https://www.mouser.de/productdetail/schurter/43000100?qs=sGAEpiMZZMv1TUPJeFpwblxZ%252bgbqW48rSymwXXVJLLw%3D)

But I wasn't able to find any filtered or switched ones, given that they are mostly used for laptops AC adapters.

In case of a classical one, which model are you recommending, probably switched as well, I don't see too much space on the back panel.

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on December 19, 2017, 06:47:15 am
I just used a cheap and cheerful Chinese switched one https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1343235/#msg1343235 (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1343235/#msg1343235)

Staying IEC made sense as most other things on my bench already have them. A little off topic but  I also got a couple of these which tidied up my bench and gear shelf a lot. https://www.ebay.com.au/itm/Black-57cm-IEC-320-C14-Male-to-3-x-C13-Female-Y-Splitter-Power-Cable-Cord/331700358437?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649 (https://www.ebay.com.au/itm/Black-57cm-IEC-320-C14-Male-to-3-x-C13-Female-Y-Splitter-Power-Cable-Cord/331700358437?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 19, 2017, 06:53:32 am
What about these guys. they are cheap cheerful AND filtered ?

http://www.mouser.com/ds/2/769/lcr082-971565.pdf (http://www.mouser.com/ds/2/769/lcr082-971565.pdf)

I just used a cheap and cheerful Chinese switched one https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1343235/#msg1343235 (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1343235/#msg1343235)

Staying IEC made sense as most other things on my bench already have them. A little off topic but  I also got a couple of these which tidied up my bench and gear shelf a lot. https://www.ebay.com.au/itm/Black-57cm-IEC-320-C14-Male-to-3-x-C13-Female-Y-Splitter-Power-Cable-Cord/331700358437?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649 (https://www.ebay.com.au/itm/Black-57cm-IEC-320-C14-Male-to-3-x-C13-Female-Y-Splitter-Power-Cable-Cord/331700358437?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on December 19, 2017, 07:01:23 am
...but checking the output of the FY6600 after it has done all its magic to produce this frequency and waveform...

This already amazed me last time, when you had the 10.123.456,78 MHz test. I would have thought that the clunky nature of the software would skip and misplace a tick every so often. But it seems that while the UI is clunky, the FPGA part is running very well disciplined. put 10.000.000,000 in, and you get 10.000.000,000 out
That means this device really can use a good reference.

As to being a Mercedes: Its still a cheap car. Just with a new state of the art ignition system.
But it is cool though, for us folk who look under the hood.

On the 3-prong plug: I just de-soldered one from the pile of junk recycle corner.
No need to buy anything fancy.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on December 19, 2017, 07:09:22 am
What about these guys. they are cheap cheerful AND filtered ?

Check the overall height? I think you may run into problems as that switch is a lot taller than the one I used.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on December 19, 2017, 03:30:27 pm
I scavenged a 3 prong from a dead PC PS which allowed me to keep the original switch.  The downside was a bunch of fiddle to fit a scrap of the PS case as reinforcement for the back panel.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on December 19, 2017, 03:48:14 pm
Similar. But I did at least put some insulation for anti-touch.
Because I suspect I may be busy inside the device more then outside it  :P
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on December 19, 2017, 05:02:24 pm
Yeah.  But mine borked itself before I got the screws back in the case.  I'd run it for a few hours on the bench with a scope and counter hooked up looking at various signals., particularly the ground to ground voltage.  Turned it off and went to bed.  Next day the UI was buggered.  So not much incentive to complete the task until I get a new front panel.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: ArthurDent on December 19, 2017, 07:08:49 pm
Changing the A.C. connector on the back of the FY6600 from a 2-wire to a 3-wire is a very good idea but I don’t see an advantage to getting a connecter/filter. Almost every SMPS has a built-in filter so adding another one wouldn’t hurt but I see no benefit. Even the crappy existing SMPS that came with the FY6600 has a capacitor across the input and a common mode dual inductor in series with the A.C. line and that would probably be acceptable but if you replace the crappy SMPS with a good one it will have a filter that probably would be identical to the Mouser LCR-082 that was mentioned.

Here is a schematic of a generalized SMPS showing a typical built-in line filter with the Mouser filter as an insert to show how alike they are. All the SMPSs I tried had a well-designed input filter like the ones shown as well as inductors in the output lines for additional filtering.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on December 19, 2017, 07:20:33 pm
Indeed, you can see that filter on the photo's above: the black/copper colored horizontal coil on the left, above the yellow capacitor, and to the right of the white connector.

I did add a ferrite beat myself, because I had them anyway, and also I was fighting noise on my scope at that time.

(Turned out to be the 1200x300 office LED panel attached to the ceiling. Weird, because that was not a china purchase but an expensive one bought from a professional office outfitter. just goes to show: if you pay a lot, you may still get the Chinese crap, just someone else has a big margin for putting on a label)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: ArthurDent on December 19, 2017, 08:20:21 pm
Cybermaus, your story about the overhead LED lighting causing interference reminds me of a slightly off topic story that is somewhat the same. A guy I met while hiking the Appalachian Trail and I would see each other every few years at some of the yearly hiker gatherings. He had lost his right arm above the elbow many years before and had a hook for his right hand. He was so adept at using the hook that he could open pop-top beverage cans with ease. Once when we were at one of these events sitting around enjoying an adult beverage he told me about how he had been involved with some of the early experiments on using nerve impulses to control a more natural looking robotic arm. He told me that one of the problems the designers ran into on the early prototypes was that when he would walk under a florescent light fixture that the RFI from the light would cause the robotic arm to go crazy and lurch uncontrollably.  Some shielding of the arm electronics cured that unforeseen problem. I still smile when I visualize him walking under a light.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 19, 2017, 08:23:04 pm
If everything goes OK, this guy will be able to fit in (kindly please confirm it for me, if anyone has an open case), and I trust more its medical device and test instruments rated filter and the dual pole switch, if I've seen correctly the original switch only breaks one wire, and I have a feeling that I'll be busy inside as well and it's not impossible that I'll replace the original PS:

http://www.mouser.com/ds/2/355/FN%209264-1036108.pdf (http://www.mouser.com/ds/2/355/FN%209264-1036108.pdf) looking at the 1A version: FN 9264-xx-1-06-y

On the other side, I think I've really scared my distributor, because I've told them that if I got one with a bad firmware they will suffer a lot, and I think they wait for a new lot with updated firmware. Or of course they are just rectums.

Finally I'm thinking of replacing the back panel with a piece of nicely anodized aluminum, do you think it's a good idea ?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 20, 2017, 05:44:42 am
Hey, look what I've found thid morning in my Inbox (chinglish spelling and grammar unaltered):

Quote
Dear customer,
Hope you rae doing fine.
Thank you for your question.
Okay. Sure. The item owns the latest 3.2 version.
Have great day
Best regards

So did anyone ever see this elusive 3.2 firmware version, should I go for it ?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on December 20, 2017, 06:12:28 am
From the Factory on the 4th of November "The latest firmware of the instrument is version 4.2 ."

Also

"DC deviations can only be corrected by updating firmware. " which as per an earlier post of mine isn't quite correct. What I suspect they mean is we have a rough stab at the trimpots then correct it in software.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 20, 2017, 06:25:39 am
Really, this is actually from Feeltech  :wtf: ?!?!?

Bloody hell, as Lucifer said,  time to have a serious conversation with those guys :box:, thanks for sharing.

 So about the DC bias, it's actually stable but it has an offset against the programmed value that needs to be compensated in SW, or it drifts away while operating ?

 Thanks,
 DC1MC

From the Factory on the 4th of November "The latest firmware of the instrument is version 4.2 ."

Also

"DC deviations can only be corrected by updating firmware. " which as per an earlier post of mine isn't quite correct. What I suspect they mean is we have a rough stab at the trimpots then correct it in software.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on December 20, 2017, 06:34:00 am
Since I sorted the bias it has stayed close to what it was set at allowing for tempco etc.... Certainly a lot better than when I got it.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 20, 2017, 06:44:50 am
Counter reply form the distributor:

"Hope you are doing fine.

Oh, sorry. The factory staff said the device embraces 3.2 firmware version, and it's the latest version at present.
Hope you could udnerstand that.

Have a great day
Best regards"
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on December 20, 2017, 07:07:19 am
Well someone is in error then  ::)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 20, 2017, 07:15:30 am
The plot thickens, I've send them the picture (and also made myself an inquiry to Feeltech), and reminding them about warranty law in Germany (they'll have to support the costs of updating), let's see what comes out of it.  Maybe dome price decrease  >:D.

 Thanks a lot,
 DC1MC

Well someone is in error then  ::)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on December 20, 2017, 08:15:55 am
Could be a simple typo. 3 vs 4 would make them both claim 3.2. I hope you are not under the impression a lot of effort and care went into that email.
I would find 3.2 more believable then 4.2, as everyone else in seemed to have gotten 2.9; 3.0; 3.1 devices

Of course, I would not recommend buying the device anyway. Not rewarding Feeltech until they do some actual warranty repairs rather then promising them.
Mine is still working, but every time I turn it on I worry.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: jleg on December 20, 2017, 11:55:16 am
I'd also say this is a typo - 3.2 seems to be confirmed from various sides, and i never heard from a 4.x version...

Btw, Feeltech requested my seller's name/address, because they "will help me to handle it". What ever that means, it does not sound like "we'll send a new front panel"...
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Mr. Scram on December 20, 2017, 11:59:09 am
The plot thickens, I've send them the picture (and also made myself an inquiry to Feeltech), and reminding them about warranty law in Germany (they'll have to support the costs of updating), let's see what comes out of it.  Maybe dome price decrease  >:D.

 Thanks a lot,
 DC1MC
Why would Feeltech be bound to German warranty laws?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Diabolo on December 20, 2017, 12:20:04 pm
Hello,

Have customs taxes been paid ?

Diabolo
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: khach on December 20, 2017, 12:55:48 pm
I that any hardware difference between 60MHz,50 MHz, 30 MHz and 15 MHz version of  FY6600? Is low frequency version upgradable by hack  to  high frequency version?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 20, 2017, 08:08:52 pm

Why would Feeltech be bound to German warranty laws?
[/quote]

Feeltech couldn't give a rat behind about German warranty laws, the seller of the device on the other side does, because it sells this stuff form inside Germany, with VAT and invoice.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 20, 2017, 08:10:40 pm
Most certain is a typo, but I wanted to have them admit that they will support the upgrade expenses if it's not the right version (I have doubts that is even 3.2), we'll see.

Could be a simple typo. 3 vs 4 would make them both claim 3.2. I hope you are not under the impression a lot of effort and care went into that email.
I would find 3.2 more believable then 4.2, as everyone else in seemed to have gotten 2.9; 3.0; 3.1 devices

Of course, I would not recommend buying the device anyway. Not rewarding Feeltech until they do some actual warranty repairs rather then promising them.
Mine is still working, but every time I turn it on I worry.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 20, 2017, 08:13:04 pm
I that any hardware difference between 60MHz,50 MHz, 30 MHz and 15 MHz version of  FY6600? Is low frequency version upgradable by hack  to  high frequency version?

Could be, but now the price difference is that small that it's not worth the effort to lose the warranty (the firmware isn't fully stable yet) and hack it for ca. 18-20EUR gain.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 20, 2017, 08:14:12 pm
Huh ?!?! What are trying to say here ?


Hello,

Have customs taxes been paid ?

Diabolo
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Chris56000 on December 26, 2017, 05:46:48 pm
Hi!

Has anybody tried modernising their FY6600 with one of these:–

https://m.ebay.co.uk/itm/New-Multi-channel-Linear-DC-Power-Supply-Module-3-3V-5V-12V-Adjustable-Output/262612931341?hash=item3d24f3530d:g:ZgYAAOSw8oFXz3Vu

Are they capable of supplying the necessary power requirements of the unit? I'm thinking of replacing the cheap and horrible SMPSU with one of these linear modules with the advantage of transformer isolation!

Chris Williams
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Mr. Scram on December 26, 2017, 05:50:06 pm
Hi!

Has anybody tried modernising their FY6600 with one of these:–

https://m.ebay.co.uk/itm/New-Multi-channel-Linear-DC-Power-Supply-Module-3-3V-5V-12V-Adjustable-Output/262612931341?hash=item3d24f3530d:g:ZgYAAOSw8oFXz3Vu

Are they capable of supplying the necessary power requirements of the unit? I'm thinking of replacing the cheap and horrible SMPSU with one of these linear modules with the advantage of transformer isolation!

Chris Williams
I think you'd have to ask yourself whether you really want to hook up an unmarked and unknown Chinese power supply to mains.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Diabolo on December 26, 2017, 07:12:04 pm
Hello,

This power supply will do the job by adding an internal transformer, or external power supply.
- https://www.banggood.com/fr/DIY-USB-Boost-Single-Turn-Dual-Power-Module-Linear-Regulators-Multiple-Output-Power-Kit-p-1022517.html?rmmds=myorder&cur_warehouse=UK (https://www.banggood.com/fr/DIY-USB-Boost-Single-Turn-Dual-Power-Module-Linear-Regulators-Multiple-Output-Power-Kit-p-1022517.html?rmmds=myorder&cur_warehouse=UK)
- https://fr.aliexpress.com/item/New-Arrival-DIY-Power-Supply-Module-USB-Boost-Single-Turn-Dual-Linear-Regulated-Power-Kit-Regulator/32695921692.html?spm=a2g0w.10010108.1000014.24.32b7a9aOyqOWH&traffic_analysisId=recommend_3035_null_null_null&scm=1007.13338.80878.000000000000000&pvid=506d4eea-89c5-4977-9f9d-77e306085a91&tpp=1 (https://fr.aliexpress.com/item/New-Arrival-DIY-Power-Supply-Module-USB-Boost-Single-Turn-Dual-Linear-Regulated-Power-Kit-Regulator/32695921692.html?spm=a2g0w.10010108.1000014.24.32b7a9aOyqOWH&traffic_analysisId=recommend_3035_null_null_null&scm=1007.13338.80878.000000000000000&pvid=506d4eea-89c5-4977-9f9d-77e306085a91&tpp=1)

(http://img15.hostingpics.net/thumbs/mini_871590Alimentationsymtrique.jpg) (http://www.hostingpics.net/viewer.php?id=871590Alimentationsymtrique.jpg)


Diabolo
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Chris56000 on December 26, 2017, 09:15:25 pm
Hi!

Quote
https://www.banggood.com/fr/DIY-USB-Boost-Single-Turn-Dual-Power-Module-Linear-Regulators-Multiple-Output-Power-Kit-p-1022517.html?rmmds=myorder&cur_warehouse=UK/quote]

I'd certainly go with one of these (bought in kit form so I can document the schematic & parts list of course!!!) and have been thinking about one – I've got an RS 78xx PCB floating about to fit rectifiers & smoothing capacitors to!

Does anyone know the approximate current consumption of the FY6600 (per rail) driving 10V p–p square @ 1 MHz into 50 ohms ?

Chris Williams
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 26, 2017, 10:42:47 pm
Hi!

Has anybody tried modernising their FY6600 with one of these:–

https://m.ebay.co.uk/itm/New-Multi-channel-Linear-DC-Power-Supply-Module-3-3V-5V-12V-Adjustable-Output/262612931341?hash=item3d24f3530d:g:ZgYAAOSw8oFXz3Vu

Are they capable of supplying the necessary power requirements of the unit? I'm thinking of replacing the cheap and horrible SMPSU with one of these linear modules with the advantage of transformer isolation!

Chris Williams

Hi Chris, the idea of using an analog power supply it's excellent, I'll do it my self as one of the last steps of modding the FY into a better instrument, the mains isolation and lack of SMPS noise it's a great thing to have if the transformer and caps are fitting in the box. But the posted power supply looks really bad, the 12V AC secondary and the 2 anemic filtering caps will not produce such a good power.
UPS finally send my tracking number and in max two days mine will reach me, I'll do the power measurements but there is no way this PS will sustain 10Vp-p on a 50ohm load, IMHO.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 27, 2017, 10:12:39 am
In preparation to the big communication protocol reversing, before my device and LA arrives, I have a request for the people who can still open their FY and do some measurements:

 - By looking at the posted pictures and videos, it seem that the flat cable caries 2 things:
 
- 1 Serial Interface that goes to the signal board serial to USB connector.
- And the 8 (?!?!) bit parallel (?!?!) bus for configuring the the generator.

I have the following questions:
- The parallel bus has really just 8 wires, I may have miscounted looking at the pictures ?
- Has anyone put an oscilloscope on this bus, has the communication been identified or at least if there's some clock, R/-W pin and similar,  is the bus bidirectional or there are separate Is and Os ?

Also one administrative question: should we keep one of the current threads alive with this project (either this one or the one with the firmware flashing) or should I create a new thread ?

I soo much wish that the UPS guys will move a bit faster  :scared:

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on December 27, 2017, 01:42:15 pm
 I located a clock and events when I pressed buttons  The ribbon has 12 wires, four of which appear to be for the RS232 connection. IIRC I only observed data on 3 lines + the clock.  That suggests that every other line is ground.

I did not have a reliable connection to the bus, so I stopped until I have time to put an attachment for probing together.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 27, 2017, 01:52:46 pm
I located a clock and events when I pressed buttons  The ribbon has 12 wires, four of which appear to be for the RS232 connection. IIRC I only observed data on 3 lines + the clock.  That suggests that every other line is ground.

I did not have a reliable connection to the bus, so I stopped until I have time to put an attachment for probing together.

Cool, now it's the time for Captain LA to save the day  :box: !!!

Before I'm engaging in more (possible destructive) testing on the FP firmware I want to fully decode the protocol, especially if there are calibration constants stored in the FP firmware.
Once this is done, then there is no stress if the firmware goes puff, I was thinking anyways to move the signal board in an re-purposed scope box that has an encoder on FP and enough buttons.
Also, once the programming of the signal board it's fully reversed, a better LCD control unit can be connected, eventually a repurposed tabled with touch screen.

I'm biting my fingernails waiting for the boxes wit the FY and an LA, let's see what UPS is doing.

 



Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on December 27, 2017, 02:13:12 pm
If you have the connector parts make yourself a 1x8 jumper cable with probe points.  I just got the connectors a couple of days ago, but I'm cleaning and reorganizing my work space (and I've got a remodeling project I need to get back to work on).  I just got my MSO-2204EA a month or so ago and am still in the process of tooling up to use it. The last time I did this everything was through hole DIPs, but those probe clips aren't much help with SMD parts.

You *might* be able to separate the factory cable wires and attach probes, but there's not a lot of slack.  I stuck the probe leads down into the back of the generator board connector but that was not a very secure connection.  I got a kit of "dupont" cable connectors from eBay and will make up a complete set of 1xN M-F probing jumpers some evening soon.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: nctnico on December 27, 2017, 05:22:55 pm
I located a clock and events when I pressed buttons  The ribbon has 12 wires, four of which appear to be for the RS232 connection. IIRC I only observed data on 3 lines + the clock.  That suggests that every other line is ground.

I did not have a reliable connection to the bus, so I stopped until I have time to put an attachment for probing together.
What works well for me when probing many signals is a dual row header with enamel wires attached to it. One row are for signals, the other row is for ground. I solder the enamel wires to the board because clips let go way too easely.
(https://farm5.staticflickr.com/4690/38627635874_d6d5695767_z.jpg) (https://flic.kr/p/21RoJnY)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on December 27, 2017, 06:25:47 pm
Certainly the way to go if you need to connect to a PCB.  Sadly, to be useful with an MSO-2204EA I'll have to repackage the LA probes to use a 2x8 header.  I've planned to do that, but have other mischief I want to do first.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 27, 2017, 07:11:50 pm
Well, now we have to get Cybermaus, and the other guys that suffered, on board. Time to spend some calories on something more advanced than replacing capacitors.
On connecting side, I have a crimping female FRC connector, if by chance the cable fits than that's it, if not I will pierce the isolation with some needles, if somebody know if there are some "vampire" grippers for small wires, now it will be a good chance to tell about them, and better be available in EU or I'll pester the US guys here to send me some in an envelope ;).

Three signals plus clock, I'm wondering what kind of contraption is there, could it be two synchronous independent channels, I 'm really wondering if the communication is bidirectional and how it's implemented.
Finally something interesting to play with, I so much wish to get on board someone with one of this advanced LAs, with a gadzillion protocol decoders.

Oh well, not much to do until the stuff arrives, I'll keep on eye here and read something more about the STM32.

I've still didn't hear the thread option, should we stay on this thread when the work starts or should I create a new thread specialized for this project ?
Here's a picture of my cat looking forward to participate on the project as a source of entropy  >:D.


 Cheers, DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 27, 2017, 08:59:30 pm
For the STM32 experiments bought myself a pair of these (one will become a controlled SWI debugger to test some of the Fraunhoffer guys experiments) :

https://www.ebay.de/itm/282786310657 (https://www.ebay.de/itm/282786310657)

Anybody has a recommendation for a non-castrated C development environment, based on GCC if possible ?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on December 28, 2017, 12:30:15 am
The STM32F429 Discovery kit includes a 320x240 touch screen for $24 US the last time I checked.  At any rate, the chips are so good, you can't have too many.

ST offers a full dev kit and there is the gcc toolchain, so everything you need several times over.  You might want to look into Matthias Koch's Mecrisp which is an approximately ANS forth of superb quality.

ST provides a large suite of examples and libraries for their devices.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 28, 2017, 12:34:31 am
I've bought the little boards not because there weren't any other more interesting or more capable, but because I needed something that has the same chip variant as the FP MCU of the FY.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: texaspyro on December 28, 2017, 01:30:44 am
Or instead of keeping with the ARM, maybe a Arduino 2560 or other Atmel CPU.   That way there is no arguing about copyright issues.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: g0mgx on December 28, 2017, 06:56:56 am
I've bought one of these units and have done some quick tests and it seems I have some wierd DC offsets in the waveforms above an amplitude of 0.5Vpp (as set on the instrument itself):

https://g0mgx.blogspot.co.uk/2017/12/feeltech-6600-another-one-really.html (https://g0mgx.blogspot.co.uk/2017/12/feeltech-6600-another-one-really.html)

Anyone else seeing this?

I've managed to "break" the software a few times and needed a power off-on to get it going again. There is certainly a firmware bug around 0.5V amplitude where a relay goes clunk inside the box; sometimes sometimes that step from below to above 0.5V can be huge even when the adjustment in amplitude made is in the decimal points of the value.

And for sure the manual states that the outputs are 50 ohm but the amplitude setting and the measurements at 50 ohm have little or no resemblance to each other.

Anyone else seeing the same thing?

Mark
G0MGX
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 28, 2017, 08:53:33 am
Hi Mark, what is the firmware version of your unit ?
There were other reports of strange DC offset, but FeelTech claims that this is fixed in fw. version 3.2

The calibration constants and all the necessary math are (allegedly) stored and done in the Front Panel little MCU, and the firmware there has lots of bugs, it could be that the MCU they've chosen doesn't have enough resources.
 
I hope you can participate in the effort to reverse and understand the communication protocol between the front panel and the signal board.
The signal board is reported reasonable good as-is, and can be made better with inexpensive modifications.
My unit it's finally "in delivery" and will reach me today, so I will contribute also reports.
Also when my LA will reach me, I will start working on the communication protocol, but I need other owners to look on the bus so we can compare results.

  73 de DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Yansi on December 28, 2017, 11:33:51 am
Hi!

I have just gone through the whole thread. Interesting device this is.

Can somebody please enlighten me how the output amplitude control is done in this device?

Thx, Y.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 28, 2017, 12:20:17 pm
My FY6600 arrived, the piece of excrement Chinese distributor send one with firmware 3.1, solidifying my opinion that they are scum of the Earth.  |O :palm:
Of course after confirming in their crappy Chinglish that their devices have 3.2, you've seen the exchange somewhere else in the thread where that was a question about a version 4.2.

I'm asking for your opinion, what should I do, should I send it back as is or should I start working on it.

I don't care about their firmware shit, but I needed one with a (semi)decent fw. to not get their stupid mistakes in configuring the generator, decoding and extracting the firmware it's a lot of work and I don't want to do it twice. and this seem to be the firmware that does not fuck the display but has some numerical errors in setting the DC offset and signal level, exactly the stuff I wanted to have.


Is there somebody with a version 3.2 and a Logic Analyzer willing to reproduce my steps here to decode the protocol (nothing will be done on the firmware extraction until the protocol it's fully understood, so it should be relatively safe) and compare the results ?
Please let me know about your opinion.

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 28, 2017, 12:30:30 pm
Hi!

I have just gone through the whole thread. Interesting device this is.

Can somebody please enlighten me how the output amplitude control is done in this device?

Thx, Y.

I was planning to do a schematic capture today, while replacing the crapacitors, not sure if I'll do it or I'll be waiting for the one with the 3.2 firmware.

Anyway, a schematic will be done.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Yansi on December 28, 2017, 12:37:35 pm
OK thanks.  I have noticed the DAC904 has an external VREF input and someone have noticed there are some Microchip DACs like MCP4821 or what. I think they obviously use these to set the VREF of the DAC904, which makes sense.

(In the neighbouring thread about the JDS6600 generator, they use a 4quadrant multiplier to do it and I was curious abotu the solution in the FY6600.)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: kahe40 on December 28, 2017, 02:21:28 pm

a firmware bug around 0.5V amplitude where a relay goes clunk inside the box ...


no problem at all with v3.1     (push SYS, maybe you have v3.0)

< 1mV it is not really perfect, e.g. 200uV positive and 400uV negative sinus,
but from 1mV upwards everything is perfect



Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: g0mgx on December 28, 2017, 02:55:51 pm
My firmware is V3.2 (thats what is reported on boot and in the SYS screen).

There are quite a few issues with the software all of which seem to be fixed by a mains cycle.

Another issue I have found with my unit is that **sometimes** if you power it off with a 0.5V amplitude using the soft power switch on the front, when you switch it back on again there is no output until you increase or decrease the amplitude; it then works fine at the 0.5V setting.

I wonder if I have a sticky relay or two?

I need to read through the whole thread - but it's very long now - happy to get involved in the decoding of comms.

Mark
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on December 28, 2017, 03:02:52 pm
I had proposed an instrument wiki so that we could organize such things more easily.  I'd love to be able to read a summary of the $20 LCR thread, but at 170+ pages it's just too long.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: g0mgx on December 28, 2017, 04:19:54 pm
I've now read the entire thread and have taken the PSU board out of mine to take a look at the caps.

The 10uF 450V cap in mine has only one leg soldered to the PCB, so I don't think that will have been helping much  :palm:

I've already changed the mains socket for 3 pin type and connected the mains earth to the 0V line; saves doing this with my PC and a USB cable instead. I'll change all the caps in the output for 25V types and see what happens.

Mark

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on December 28, 2017, 06:20:51 pm
You may want to reinforce the panel.  Your mount is like mine and when I pushed a cord on, it deflected too much to be comfortable. So I took it apart and added a metal brace scured by hot melt glue to the bottom of the case.  The socket screws thread into the metal which was cut from on old PS case.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 28, 2017, 07:40:06 pm
Hi, these are the latest news, my fw. is indeed 3.1, I've contacted the seller that hasn't responded yet and "suddenly" all the available 60MHz units are not available anymore, just some 30MHz.
I was able to read the CD, it seem to be some software for more models and due to some family obligations I wasn't able to do more.
I seem that my LA will be delayed to the next year as well :'(, so I have to use my 4 channels Tek to try to get some data out of the bus, if I don't send the device back. Really, I wish that seller and his company to have 4 as a number for 10 years and  live trough the most interesting of times.
I'm so happy that there is someone with a 3.2 software willing to sniff the bus as well, I will try to hook the scope tomorrow and see what is coming out.
And Feeltech, I know that you're monitoring the thread, do try to get some (half)honest distributors, you will lose face and crash your momentum, you've managed to anger a large part of your customer base.
See you tomorrow, DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on December 29, 2017, 12:11:24 am
My last communication from FeelTech :-(

--------------------------------------------------------------------------------------------------------
Re:FY-6600 V3.0 FW problem
Thursday, December 21, 2017 3:51 AM

From:
    "????" <admin@feeltech.net>
To:
    xxxxxxxxxxxxxxxxxxxxxxxxxxxxx

We will deal with it as soon as possible to keep you waiting

---------------------------------------------------------------------------------

No response at all from the seller since this:

---------------------------------------------------------------------------------------------------------------
Friday, December 8, 2017 11:40 PM

From:
    "eBay - sportgogo" <sportg_gx3808oho@members.ebay.com.hk>
To:
   xxxxxxxxxxxxxxxxxxxxxxxxxxxx

sorry for this,we will check with supplier,please don't worry.
best regards,
 
---------------------------------------------------------------------------------------------------


Needless to say, I am not happy.  It is very hard to believe there is a good faith effort being made.  In fact, I don't believe *any* effort is being made.  So I think complaints to eBay and PayPal are in order.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: armrisc on December 29, 2017, 02:25:09 am
Hi guys! My firsts post here. I'l read about this generator for a while and i started to realy like it. Expecially external trigger is realy usefull for my uses(in contrast to JDS6600) At the start i was looking at the Rigol DG1022, but for a hobbyist - price is to high for my liking, so Fy6600 is like a superb new year gift for mysefl. :)
The reason I registered is regarding firmware - mainly problems with it - display corruption, not possible to reflash it localy etc. What concerns me the most is why this corruption ocurrs? You can avoid problems if you know reasons, but at this point it's a black hole.
I read through all posts, maybe missed it. As far as my understanding goes it only can be related with waveform upload, this is the only time write to chip is happening?, or is it memory overflow,bug  issues and with time you will be hit by corruption anyway? Returning device to manufacturer for me is is a no-go, I can by a new item for the same cost. Any ideas anybody?
Thanks in advance.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on December 29, 2017, 02:57:26 am
I modified mine to add a grounded power cord as my scope showed 176 Vpp from the BNC to earth ground.  I closed it up and it sat on the bench hooked up to a scope and a frequency counter for a couple of hours.  Everything was fine.  I shutdown the lab bench and went to bed.  The next day I powered it up to do some more experiments.  Display was borked.  It mostly works, but several waveforms stopped working entirely.  At power up it sets very strange values which *are* the correct values for the output.  My screen looks exactly like the photos in the first post of the reflashing thread.  Another owner tried to reset to factory defaults.  That made the unit completely non-functional.

I never got as far as trying to load a waveform.  The consistency of the failures of the V 3.0 devices indicates it's a serious software error.  It is known that 3.1 has problems and there is a growing suspicion that 3.2 also has a problem, though the extent of issues with 3.2 is not yet well known.

My post earlier today should give you a pretty good idea of the current support situation.  You *really* don't want one of these until FeelTech provides replacement front panels to affected owners.  Unless, of course, you're looking for a repair and hacking project.  Those of us with borked units would love help figuring out how to fix them.

These are *not* getting borked by the users doing something wrong.  They are failing because there is a FW error which FeelTech knows about.  They have updated the FW twice, but have not provided any fix for units in the field.  Lots of promises, but no action.  Returning a failed unit to China will cost $30 from the US.  There is no guarantee you'll get *anything* back.  So returning it is just throwing good money after bad.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on December 29, 2017, 03:30:16 am
As I have mentioned before in this thread and given the numbers of firmware failures of these time for Feeltech to come up with a method of user upgrading.

Continual placing of their heads in the sand over this will see a severe decline in sales as any quick Google check of their product will get you here!
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Chris56000 on December 29, 2017, 04:56:15 am
Hi!

I've just been advised by Royal Mail that delivery of my unit is expected by 9 Jan – I've no problems with that as I ordered mine for delivery to my work address and I'm not back on duty till Tuesday the 2nd!

Funny the 60 MHz units all seem to be suddenly "out of stock" or "unavailable" tho' – this does make me wonder if the maximum sine frequency is both a hardware and a firmware change!

(I can't afford to buy a unit of each frequency–spec. to see what the differences are!)

Regrettably I've little or no experience on extracting communication protocols, having never had reason to need to do it, but I will do what I am experienced at, namely providing a set of full schematic diagrams!

I do have one question tho' – are the "waveform graphics" shown on the front display/U.I. actually drawn/calculated from whatever is sent to the DAC controls, or are they a simple graphic plot worked out from a library function table, etc?

Chris Williams
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: g0mgx on December 29, 2017, 06:39:10 am
I do have one question tho' – are the "waveform graphics" shown on the front display/U.I. actually drawn/calculated from whatever is sent to the DAC controls, or are they a simple graphic plot worked out from a library function table, etc?

The graphic on the screen changes with waveform and if applicable Duty, no changes with amplitude, offset of phase. Both Ch1 and Ch2 waveform types appear regardless of the on/off status of the channels.

Mark
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: g0mgx on December 29, 2017, 07:08:21 am
I am rapidly concluding that the bug list in this device is way longer that any of us realise.

This morning I have tried two identical signals 90 degrees out of phase; they measured about 83 degrees apart. Then a quick power on off corrects this issue but now the channel 2 signal has the weird DC offset I reported previously on Ch1  but Ch1 is centered around 0V correctly. With both channels the same (using the "Sync" feature) at 10MHz and an amplitude of 0.5V, a soft power off guarantees neither channel will start on power on until you alter the amplitude of each one away from 0.5V.

(http://qsl.net/g/g0mgx//BlogFiles/FeelTech/outofphase.png)

(http://qsl.net/g/g0mgx//BlogFiles/FeelTech/2chsync.png)

(http://qsl.net/g/g0mgx//BlogFiles/FeelTech/2chsync%20II.png)

(http://qsl.net/g/g0mgx//BlogFiles/FeelTech/DSCF4050-Optimized.JPG)

(http://qsl.net/g/g0mgx//BlogFiles/FeelTech/DSCF4051-Optimized.JPG)

I'm rapidly drawing conclusions on this unit, especially around the amplitude setting of 0.5V where **something** weird seems guaranteed every time  |O

Mark
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: CustomEngineerer on December 29, 2017, 07:29:07 am
Continual placing of their heads in the sand over this will see a severe decline in sales as any quick Google check of their product will get you here!

I'll believe it when I see it. These units have had major issues since day 1 (that feeltech still hasn't addressed), but people continue to buy them anyways.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Mr. Scram on December 29, 2017, 08:03:19 am
Just to be sure, but did you properly terminate the cables? Weird phase shifts can be sometimes seen in unterminated cables, though I'm not sure the frequency is high enough for that.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on December 29, 2017, 08:49:15 am
Continual placing of their heads in the sand over this will see a severe decline in sales as any quick Google check of their product will get you here!

I'll believe it when I see it. These units have had major issues since day 1 (that feeltech still hasn't addressed), but people continue to buy them anyways.

It is a shame as the built in feature set with a few on going hardware improvements from there end would see market dominance in this lower priced Sig Gen market. Open Source the software/firmware and remain the hardware provider and take advantage of a user base modding and tweaking would be a win win for them.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: g0mgx on December 29, 2017, 08:56:06 am


Just to be sure, but did you properly terminate the cables?
Yes, the 'scope is 50R terminated in both channels.

I've created a video of my issues (well only some of them)

https://g0mgx.blogspot.co.uk/2017/12/feeltech-6600-issues-list.html (https://g0mgx.blogspot.co.uk/2017/12/feeltech-6600-issues-list.html)

I can't help thinking that what I am seeing is a combination of firmware and possible some crappy relays sticking.

Anyone with the same unit, can you reproduce what I show on the video?

To confirm the firmware in my unit is 3.2.

Mark
G0MGX
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 29, 2017, 09:16:16 am
Hi, just some replies on topics, in no specific order, of course everything is IMO and IMMV:

- The people still buy it because for the price is by far the best option of a signal and AWF generator, the signal board is decent but controlling part is crap, they've chosen a way too weak MCU that does way too much. And the original, non-copied Chinese software still has a lot to catch, the hardware production was outsourced in China, not the software (that was outsourced in India).

- The distributors and FeelTech are in between a rock and a hard place, even with Asian production costs and sponsored shipping to EU/US, I believe the margins are not too big. And shipping from EU/US to China is NOT sponsored, to every repaired unit will bring them a net loss. Not to mention that the firmware is way too unstable and more than one trip will be needed, even if they will release the firmware, the unit needs serious modifications to even be capable of upgrade, it still could be possible that there is some way to do it over the exposed serial interface and FeelTech are just a-holes not willing to release the firmware.

In the end they will probably design another unit, a bit better and leave the ones who bought the FY6600 hanging dry. So the effort to reverse and open source the protocol/fw may or may not succeed, who wants official vendor support for this model is probably out of luck and should try to return them while still possible.Who decides to keep the unit, either because it likes it or it does modifications that voids the warranty should better start hooking the logic analyzers and draw schematics, I'll do it, because I've promised to do it and I see some value in the signal board.

DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 29, 2017, 09:18:20 am


Just to be sure, but did you properly terminate the cables?
Yes, the 'scope is 50R terminated in both channels.

I've created a video of my issues (well only some of them)

https://g0mgx.blogspot.co.uk/2017/12/feeltech-6600-issues-list.html (https://g0mgx.blogspot.co.uk/2017/12/feeltech-6600-issues-list.html)

I can't help thinking that what I am seeing is a combination of firmware and possible some crappy relays sticking.

Anyone with the same unit, can you reproduce what I show on the video?

To confirm the firmware in my unit is 3.2.

Mark
G0MGX

Hi Mark, I don't believe in the sticky relay thing, I believe that most likely when they try to restore the state after stand-by, they just forget to restore thing properly in the signal board, IMO it's 100% a firmware issue.

 Cheers,
 DC1MC
 
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 29, 2017, 09:23:07 am
Continual placing of their heads in the sand over this will see a severe decline in sales as any quick Google check of their product will get you here!

I'll believe it when I see it. These units have had major issues since day 1 (that feeltech still hasn't addressed), but people continue to buy them anyways.

It is a shame as the built in feature set with a few on going hardware improvements from there end would see market dominance in this lower priced Sig Gen market. Open Source the software/firmware and remain the hardware provider and take advantage of a user base modding and tweaking would be a win win for them.

The one that will convince a Chinese company to open-source and deobfuscate the specs of one of their (good selling) products will be remembered for ever as a hero and saint, it's so opposed to their culture that it's almost impossible, the specifications, protocols and everything must be reversed and extracted with great pain if someone wants them.

On the other side, profiting form OSS and public knowledge and not giving anything back, hell yeah, that makes good business sense, "they are giving this sh..t for free, let's use it..."
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Yansi on December 29, 2017, 11:15:24 am
they've chosen a way too weak MCU that does way too much.

Any proof of that statement? I think that this is only empty screaming around.  72MHz Cortex M3 is pretty adequate to control a decent DDS generator.

The MCU does zero to nothing, apart from reading buttons and playing with the LCD. This is simply a issue of crap FW, not weak MCU.

All the interesting magic happens inside the FPGA. The MCU just commands it with the frequency and other such settings.

Reverse engineering the schematic would be awesome. However, is reverse engineering of the FPGA-to-MCU protocol necessary? Wouldn't it be easier to make the whole FPGA content new? I can not help much with that, as I have less than little experience in VHDL (and only using small CPLDs), can only offer quite some expertise on STM32.
My idea about the FPGA does tell me, there really should not be that much in there.

But considering the amount of work required for this, wouldn't it be better to even redesign the PCB? I see a lot of room for some marginal improvments, right?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 29, 2017, 11:28:40 am
One step at a time, in order of difficulty:

 1x - Capturing the schematics, to see with what we're actually dealing.
 3x - Decoding the communication protocol and capabilities of the existing signal board / firmware.
 9x - Redoing the STM32 firmware in a proper way.
27x - Exploring and fully understanding the possibilities and limitations of the current signal board design, including the firmware.
81x - Redesigning and producing an improved FPGA firmware.
243x - Redesigning and producing another signal board with better features and performance

These are my very conservative and optimistic estimates of the difficulty multiplication factor of the tasks ahead.
One has only to provide the number of hours needed for capturing the schematics.

So, let's try to get the schematics of the existing unit to get the unit of effort (UE) in work hours for the project.

 Cheers,
 DC1MC
 
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: kahe40 on December 29, 2017, 12:40:30 pm

Anyone with the same unit, can you reproduce what I show on the video?


no such a behavior here with 30MHz model and v3.1 with Ser# 893 783 770
and a quick test (family is demanding), but You say in Your blog :

>> ... amplitude setting of 2.0V (the manual says this is "default"
>>  peak to peak - I have found no way to change this "default" setting).

try   SYS/MORE/factory default:OFF
and save several presets in SYS/SAVE/S01 S02 ...

those are my conditions, FactoryOFF
and several saved Sets, from which I start working.
Maybe in your fresh unit something is not initialized ?
Or new bugs in v3.2 ?

edit Ser#
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Yansi on December 29, 2017, 12:52:21 pm
One step at a time, in order of difficulty:

 1x - Capturing the schematics, to see with what we're actually dealing.
 3x - Decoding the communication protocol and capabilities of the existing signal board / firmware.
 9x - Redoing the STM32 firmware in a proper way.
27x - Exploring and fully understanding the possibilities and limitations of the current signal board design, including the firmware.
81x - Redesigning and producing an improved FPGA firmware.
243x - Redesigning and producing another signal board with better features and performance

These are my very conservative and optimistic estimates of the difficulty multiplication factor of the tasks ahead.
One has only to provide the number of hours needed for capturing the schematics.

So, let's try to get the schematics of the existing unit to get the unit of effort (UE) in work hours for the project.

 Cheers,
 DC1MC

Well I am aware of that this is a time consuming black hole, but I'd like to point that you should probably have some coefficients even bigger. Guessing you can do the schematic within a few hours, but you won't rewrite the STM32 firmware in just 10 hours. Maybe 50 hours, likely more. Well... lets keep us being optimistic :D
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 29, 2017, 05:13:44 pm
I would say a proper schematic capture will take at least 10 hours, rewriting the STM firmware after one has the full schematic and protocol to be implemented fully specified, it's realistic to have it in beta after 90 hours.

 DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Chris56000 on December 29, 2017, 07:48:07 pm
Hi!

Quote
I would say a proper schematic capture will take at least 10 hours, rewriting the STM firmware after one has the full schematic and protocol to be implemented fully specified, it's realistic to have it in beta after 90 hours.

I think that's a reasonable, possibly even conservative, estimate of the time needed to produce a good set of Schematic Diagrams!

I admit, as I said in a previous post, that I'm not skilled in reversing firmware or communication protocols in a given piece of unknown equipment, but I can use Member DC1MC's estimate of how long the drawing–out will take as a guide and compare how long I take with the ten hours estimated!

(I think it wouldn't be a wasted effort for more than one of us to work on the schematics as with a densly–populated analogue/digital surface–mount PCB like this it's so easy to get it wrong somewhere, which would affect the FW reversal!)

My suggestion for new firmware would be:–

1) Find out what type of LCD driver is needed for the original display and design a good U.I  (No horrible Chinese Lettering!) – Our Continental Friends may be able to assist with translations for additional languages if needed;

2) Find out how many functions need to be sent back to the main PCB for control of the Altera Cyclone;

(Waveform type selection, amplitude, frequency, phase, DC offset etc., per channel, plus one function for each Arbitrary Waveform provided – it may be possible to use the PC software provided by FeelTech to get the waveform–function for each Arbitrary Waveform provided;

3) Decide on implementation of the additional control functions – AM/FM Mod, VCF, Sync, etc;

4) Consider wether a Frequency Counter Function is needed;

5) Finally, the "housekeeping" functions – factory reset, Cal/setup, self–test, firmware-update, etc;

I certainly agree it's not trivial but I thought if I set out a rough draft of the firmware functions first it'll assist those excellent chaps on here who are much more "au–fait" with software/firmware engineering than I am!

Chris Williams
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Marco on December 29, 2017, 08:48:26 pm
If someone can read out the firmware finding the buffer overflow (or they might be slamming the flash with way too many writes I guess) shouldn't be that hard if they have IDA ... it happens frequently enough that it shouldn't take too long just triggering on memory access. Binary patch it and throw it on the internet.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 29, 2017, 09:36:33 pm
If someone can read out the firmware finding the buffer overflow (or they might be slamming the flash with way too many writes I guess) shouldn't be that hard if they have IDA ... it happens frequently enough that it shouldn't take too long just triggering on memory access. Binary patch it and throw it on the internet.

Uhmm, so which firmware version exactly are you talking about, all seem to be buggy ?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on December 29, 2017, 11:53:53 pm
Based on my bus probing, there is a pretty simple command protocol.  The UI shows the user what the current parameters are and transmits the changes. At boot time it sends the boot time settings to the AWG.  Other than an ACK/NACK, there is no reason in AWG mode for any traffic from the AWG board to the UI board.

So IMHO, the first step is to figure out what the UI sends to the AWG when you change a setting.  Forget the counter function until the AWG works.  That's the part that's valuable.  You can buy a much more capable counter on eBay for $12-15.


As for reading the FW, read the Fraunhofer paper, implement it and get back to us with the FW dump. We'll be happy to take it from there.

I've had to fix a few million lines of other people's code.  At a certain point, it is easier and quicker to simply consider the problem and write the code from scratch.  I think that is true in this case.  Using the device as an AWG only requires sorting out the command set.  I'll gladly write code to control the AWG via RS-232.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Marco on December 30, 2017, 12:09:14 am
Uhmm, so which firmware version exactly are you talking about, all seem to be buggy ?

The most severe bug, ie. the fact it trashes the program storage, shouldn't be too hard to track down with a disassembler (IDA) and debugging once you have ripped the firmware. Then you can patch it at assembly or even machine code level.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 30, 2017, 12:10:19 am
Based on my bus probing, there is a pretty simple command protocol.  The UI shows the user what the current parameters are and transmits the changes. At boot time it sends the boot time settings to the AWG.  Other than an ACK/NACK, there is no reason in AWG mode for any traffic from the AWG board to the UI board.

So IMHO, the first step is to figure out what the UI sends to the AWG when you change a setting.  Forget the counter function until the AWG works.  That's the part that's valuable.  You can buy a much more capable counter on eBay for $12-15.


As for reading the FW, read the Fraunhofer paper, implement it and get back to us with the FW dump. We'll be happy to take it from there.

I've had to fix a few million lines of other people's code.  At a certain point, it is easier and quicker to simply consider the problem and write the code from scratch.  I think that is true in this case.  Using the device as an AWG only requires sorting out the command set.  I'll gladly write code to control the AWG via RS-232.

The more I look into this stuff, the more I believe that rewriting the firmware is the best way to do it, the Fraunhofer method it's a PITA and reversing the screwed up crap in their firmware it will be most likely useless and a waste of time. I've seen that STM offers a lot of libraries for everything from serial and LCD driving to graphical and mathematical routines and I doubt that our Chinese friends used something else, new and original. And if they did, it's the buggy part. Not to mention that in this situation nobody can claim or hinder us with DMCA and copyright shite.

Now on the actual work, Rhb, could you kindly share your actual findings, which one is the clock line, what freq it used, are there direction switching signals and R/W selector or anything of importance of your findings. I will try to hook tomorrow my scope, the LA it's still on its way to me.  I should at least see how the bus it's structured physically and if I'm extremely lucky the protocol used. Hopefully more forum members will use their powerful test gear and lend a hand.

See you tomorrow,
DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on December 30, 2017, 01:12:03 am
I did very little.  I hooked up the MSO LA lines and rotated the knob.  I'd never used the LA function before, so it was mostly an instrument training session.  I'm afraid I lost my notes in the process of reorganizing my workspace.  The clock was quite slow, KHz IIRC.  My biggest problem was sorting out the MSO UI.

IIRC 0 at one side was the clock and  4, 5 & 6 or 3 were signal lines. 

I was not very happy with the LA function.  So I suggest setting single shot mode on as many lines as possible, pressing all the buttons and turning the knob.  then go to the next set of lines and repeat in a systematic fashion.

I'm jammed up the next two weeks, but will be able to work on this after that. 
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Chris56000 on December 31, 2017, 09:27:24 pm
Hi!

Quote
The more I look into this stuff, the more I believe that rewriting the firmware is the best way to do it, the Fraunhofer method it's a PITA and reversing the screwed up crap in their firmware it will be most likely useless and a waste of time. I've seen that STM offers a lot of libraries for everything from serial and LCD driving to graphical and mathematical routines and I doubt that our Chinese friends used something else, new and original. And if they did, it's the buggy part. Not to mention that in this situation nobody can claim or hinder us with DMCA and copyright shite.

I couldn't agree more!

A quick question tho' - are there standard code libraries available to enable a (reasonably nice!) text/graphical interface to be designed with choice of coloured selections for settings, functions, and a good font, such as Helvetica, Gill Sans or Frutiger? (the one the UK NHS uses for Hospital internal signage!)

(I realise Gill Sans isn't commonly found on T & M Equipment, but it does have the advantage of being clear and easy to read on graphic LCD modules!)

Better still, are there programs available that allow a U.I. to be designed by graphical means on a PC that compile source-code from this, or am I looking at a mega-costly un-affordable solution for this aspect of the firmware?

Chris Williams
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Yansi on December 31, 2017, 09:29:28 pm
STemWin. But... you better make your own library, before you adapt that bastard for a custom LCD.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 31, 2017, 09:54:43 pm
Some initial bus sniffing of the communication, VERY preliminary results:

Control connector, 8 pins, FS1

 1 - PA0 = Some kind of -POWER_GOOD, is connected to a transistor on SP with the base at 3.3V

 2 - GND

 3 - PA1 = Not found yet

 4 - PB11 = BitX FP -> SB

 5 - PB12 = BitX FP -> SB

 6 - PB13 = CLOCK, 18MHz !!!, 32 clocks/transfer.

 7 - PB14 = BitX FP -> SB

 8 - PB15 = BitX FP -> SB

So, it seem that most of statements up until now regarding the communication protocols were false, including some assumptions of mine.  :palm:

The clock is a respectable 18MHz, the data bus seem to nibble oriented, 4bits / clock, 32 nibbles  or 16 bytes or 4 x 32bits values.
No matter how small is the change ( for example just moving the encoder one position, there is a minimum of 16 transfers, or 64 x 32bit values.
So I have the feeling that each time the SB it's fully programmed, no matter how small it's the change !!!

Also barring pin 3 (PA1) doing any direction switch, the data transfer seem to be strictly from FP to SB, I have no idea how the stored waveforms are read back, if they are read.
Have a look on the pictures attached, made with my crappy TBS1104, there are 3 bits and the clock is on the yellow trace.

TODO:

 - See what is happening with pin 3, it really the transfer uni-directional ?
 - See which bit is which ?
 - Connect a proper LA (if it will ever arrive) and get a number of transfers
 - Decode the protocol and how the calibration constants are loaded.
 - The waveforms are actually stored in the SB flash and the FP just tell the SB which one to load ?

 Happy New Year !!!
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on December 31, 2017, 10:19:02 pm
The bus should have traffic to the front panel in counter mode.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on December 31, 2017, 10:25:40 pm
Could be, after I'll get my LA, I'll first try to find the bit positions, putting something like 12,234,567,890 Hz and looking at the patterns. Once the bits and transfers from FP to SB are done, then follows the frequency meter mode, prolly pin 3 will switch the direction.
I'm actually curious what is happening, but it's interesting, 18MHz clock, that's a lot for the little MCU, really interested on how it was implemented.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Yansi on December 31, 2017, 10:34:52 pm
Regarding the pins sniffed:

PB12 is likely SPI2_NSS
PB13 is likely SPI2_SCK
PB14 is likely SPI2_MISO
PB15 is likely SPI2_MOSI

As PB11 can be I2C2_SDA or USART3_RX, I'd assume it is either the RX port of UART3, or more likely a second NSS (chipselect) for the SPI.

18MHz corresponds to a PCLK divided by 2. 18MHz is nothing to be afraid of. This ain't arduino for kids. Those other  pins aroun the clock pins are definitely the SPI peripheral. There is no way it will be different. PB12 most likely the chip select signal and PB11 maybe second chip select signal.

Now you can start sniffing the data from the SPI.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Chris56000 on December 31, 2017, 11:45:38 pm
Hi!

Just a quickie one!

I've been reading the STM32F103C8 Datasheet, I was just wondering if Pins PA4 to PA7 are the ones returning from the main PCB (Altera Cyclone Arbitrary W.F. Data out perhaps?) that indicate to the STM32 MCU what waveform is being generated?

These are given in the STMJ32 Data as:-

PA4:- SPI1_NSS/USART2_CK/ADC12_IN4;

PA5:- SPI1_SCK/ADC12_IN;

PA6:- SPI1_MISO/ADC12_IN6/TIM3_CH1;

PA7:- SPI1_MOSI/ADC12_IN7/TIM3_CH2.

Monitoring these four lines whilst changing the waveform-type/amplitude/frequency, etc., using the front-panel controls would suggest this to be the case - I'm assuming these parameters are stored in the Winbond Flash, so it might be worth a continuity-prod or two to see if PA4 to PA7 on the STM32-etc., goes back to the Winbond!

Chris Williams

PS!

I've just realised Member DC1MC only mentioned an 8-pin interface connector plug between FP and SB, but there has to be another one for the 3.3V/5V supplies, earth, etc., so it's possible there may be another multi-plug with some more STM32 lines on it!

BTW, I won't get my generator at least until I'm back on duty @ work Tuesday, but I can surmise one or two things from the information already given so far!
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Yansi on December 31, 2017, 11:59:49 pm
Now there seems to be a mess in the thread.

What pins are connected in between the MCU and the other board?

Or how did you come up with the SPI1 pins?

//And note there won't most likely be any "waveform indication pins" - why would they? You have full duplex rather high speed SPI bus already there.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Chris56000 on January 01, 2018, 12:08:51 am
PPS!

Just a thought - I've just been reading Carmine Noviello's book "Mastering STM32" (V0.21), Section 20.2.1 "Flash Memory Unlocking", p. 573, where the Author clearly recommends the line:-

HAL_StatusTypeDef HAL_FLASH_Lock();

be included in the code to prevent inadvertant over-writing of the flash memory due to transients, power-faults, etc., etc., - what's the betting the Chinks (accidentally-on-purpose?!) left this line out of their code to ensure the things'd fall over before the warranty expired to try and get back development costs in the hope disgruntled users would buy replacement/upgraded/newer units?!

Chris Williams
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Chris56000 on January 01, 2018, 12:15:13 am
Hi!

Quote
Now there seems to be a mess in the thread.

What pins are connected in between the MCU and the other board?

Or how did you come up with the SPI1 pins?

The SPI1 pins are given in the STM32F103C8 datasheet pin-out table.

Member DC1MC mentioned only one 8-pin plug, none of which carry power-supply voltages, so there has to be another connector for these, so if more than two/three pins are used on a second or further connector plug, there's every possibility of there being further connections back to the MCU!

Chris Williams
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 01, 2018, 12:23:17 am
The cable between the front panel and main board is a 12 wire cable split into two groups of 4 & 8.  The 4 pin  group is  Gnd, Rx, Tx and 5V.  There are no other wires between the FP & MB.  My main board is marked V1.5.

BTW Mine was working fine for a couple of hours after I completed the grounded plug installation feeding my scope and a counter.  I shut the bench down for the night using the power strip.  When powered up the next morning it looked *exactly* like @canyon's photos at the start of the reflashing thread.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Chris56000 on January 01, 2018, 12:31:04 am
Hi!

Fair enough, Member rhb's identification of the connections rules out a direct connection from PA4-PA7 back to the WinBond, and also indicates the 3.3V reg for the STM32 will (or should be!) on the front panel PCB.

That does suggest the data control interface on lines PB12-PB15 could possibly be bi-directional, I don't think Tx and Rx will be anything like fast enough to carry waveform parameter data back.

I'll get started on a FP schematic as soon as I get my hands on my unit when I'm back at work!

Chris WIlliams
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 01, 2018, 12:35:30 am
SU1 on the FP board is an AMS1117 3.3 V LDO regulator.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Yansi on January 01, 2018, 12:58:58 am
Hi Chris,

have you read what I have written or are you deliberately ignoring my posts? I have already written you that SPI2 is used and identified the pins accordingly.

I do not know where did you get that those pins PA4 to PA7 are used in the FY6600 to communicate with the FPGA board. Or have I missed a post about them?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 01, 2018, 01:35:26 am
On my device there are 2 separate cables between FP and SB,

One 4 pin, J1
5V
GND
TxD
RxD

And the 8pin data cable that does not carry any power, it just have a GND wire.

The clock and data pins I have described in previous post.

I will see when my LA will arrive if the protocol is a variant of SPI or some other non-standard, simpler stuff. Even if the Intronix it's a bit old, it should be capable of decoding all SPI versions.
It's very likely that the SPI serializer block is used, because 18MHz it's really difficult to do by bitbanging. What it's left to see it's to see if they used the SPI interface in a sane way or in some perverted mode.
Dear members that already have a logic analyzer, please connect and determine at least the purpose of pin 3 (PA1), is it a direction switch or what.

come on, you collected all this coll gear, use it this year  :P

 
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Yansi on January 01, 2018, 01:40:10 am
Well... I don't have the FY6600 to begin wirt.  Maybe if one could donate or lend me one for reverse engineering? Germany somebody?  ;D
This way I can only give expertise on STM32 device side.

They use the SPI2 for sure. Just identify the rest of the GPIOs where do they end on the FPGA board.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 01, 2018, 01:46:34 am
Well... I don't have the FY6600 to begin wirt.  Maybe if one could donate or lend me one for reverse engineering? Germany somebody?  ;D
This way I can only give expertise on STM32 device side.

They use the SPI2 for sure. Just identify the rest of the GPIOs where do they end on the FPGA board.

There is just ONE GPIO left to be identified (PA1).
It will not survive too much afrer my LA will arrive and it will be identified ;).

On the other side, if you're close to Mannheim, I can drive to you with my FY, assuming that you have a proper LA and scope, we can even try to reproduce the Fraunhofer experiment ;).
The problem is that my LA is scheduled to arrive on 8.01, exactly when my vacation is over :(

 
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Yansi on January 01, 2018, 02:05:09 am
Thanks for your interest, unfortunately not anywhere close around Mannheim.  But Germany is the closest place where someone could have one  :)

I should be doing different things, than playing with electronics anyway... but you know it: Everything is better than to do some boring obligatory work for ... 




Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: g0mgx on January 01, 2018, 06:12:03 am
The 4 pin  group is  Gnd, Rx, Tx and 5V.  There are no other wires between the FP & MB.  My main board is marked V1.5.

The 4 pin cable is from the USB to 232 CH340 device on the main board to the FP. As far as I could tell that 5V line was the only power feed to the FP so there must be a 3.3V reg on the FP board.

Mark
G0MGX
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 01, 2018, 10:34:24 am
Gentlemen, let's focus on the important things, there is no other power line to the FP except the 5V0 coming along with the serial interface cable, the FP has 3V3 LDO  on PCB and this is that. Once I'll be able to get more friendly with KiCAD I may drawn a schematic, of I could draw it on paper faster and have some kind soul put it in his schematic capture program and produce a PDF out of it. This is really the least of our concerns here.

The data communication seem to be done over an SPI interface, that makes sense, it's bidirectional and easy to implement in FPGA. One of the signals that it's not part of the SPI interface is just a pull down transistor and another it's a mystery one that seem to stay unused at lest in the simple tests I've done.

Now, please, pretty please with sugar on top, could someone hook an Logic Analyzer on the SPI interface and get some traffic sniffed, she/he'll be my hero, because my LA coming form UK it's stuck on "Arrival Scan" and Germany it's fully stopped now :(. Come on, out of 5-6 people that spend time modding this generator it HAS to be one willing to donate a bit of time with an LA.

Waiting for good news,
DC1MC
   

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 01, 2018, 12:06:40 pm
OK, here are some more snapshots, taken with my most craptacular Craptronis scope EVAR, TBS1104, if you ever see one, destroy it with fire and a large hammer :scared: :horse:

Legend:

Yellow - SPI CLK
Blue   - PB15 MOSI
Lila     - PB12 SPI_NSS
Green - PB11 Used as another CS


There seem to be at least 2 SPI devices, form the miserable screen I just can see that there are data transfers when at least one tof the selector signals is in 0 and mone when both are 1, this is as expected
Another thing is that the word size is set to 16 bits.
And yet another thing is that there are a crapload of transfers, to just change the the last digit of the frequency  :-//.

Right now I've reached the limits of this Fully Feature-Free (TM) (C) Tektronix piece of junk, so please try to reproduce my experiments with a better scope and suggest me please a better scope in 500EUR range, this POS has to go.

Enjoy the (crappy) shots I've made with our data transfers.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Chris56000 on January 01, 2018, 12:07:05 pm
Hi!

I would like to have a go at this myself – can anyone who's a bit more "au–fait" with Logic Analyzers than I am suggest what sort I'll need – does it need an expensive "all bells and whistles" instrument that can decode the logic–bits into a hex byte, or it it possible to make up some sort of SPI decoder for the STM32 that can display the data in some form of human–readable format?

I do have an Zicon Electronics 16–channel one that displays on an ordinary oscilloscope – is this suitable for reading the SPI Lines?

Chris Williams
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: g0mgx on January 01, 2018, 12:07:21 pm
I'm happy to put some time into this, the problem is I have no experience with SPI comms and hence I dont know what I am doing.

I've attached a 'scope grab of each pin (pin 2 is ground for sure) and also the drivel I get when I try and decode this.

I'm not sure what line is CS?

If anyone wants to give me some guidance I am happy to help, otherwise I have to retreat to the sidelines and hope to learn.

I will now start a search on you tube for sniffing SPI and see what I can find.....

Pin 1:
(http://qsl.net/g/g0mgx//BlogFiles/FeelTech/Pin%201.png)

Pin 3:
(http://qsl.net/g/g0mgx//BlogFiles/FeelTech/Pin%203.png)

Pin4:
(http://qsl.net/g/g0mgx//BlogFiles/FeelTech/Pin%204.png)

Pin 5:
(http://qsl.net/g/g0mgx//BlogFiles/FeelTech/Pin%205.png)

Pin 6:
(http://qsl.net/g/g0mgx//BlogFiles/FeelTech/Pin%206.png)

Pin 7:
(http://qsl.net/g/g0mgx//BlogFiles/FeelTech/Pin%207.png)

Pin 8:
(http://qsl.net/g/g0mgx//BlogFiles/FeelTech/Pin%208.png)

Some total Drivel:
(http://qsl.net/g/g0mgx//BlogFiles/FeelTech/Pulse%20View.png)

Mark
G0MGX
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 01, 2018, 12:17:17 pm
Hi Mark, and thanks for chiming in, I was getting a bit lonely here  :-\. So, YOU WILL NOT RETREAT, YOU WILL NOT GIVE UP, you hear me  :scared:.

Now is the chance to put that gear to good use and learn a bit in the process.

So first things first, just ignore the any pins besides 4 to 8.

We don't have a really simple SPI interface here, there are at lest two, maybe three devices, most likely one is the Winbond flash.

You see on my top post what the signals are, put MISO as well, and set the logic analyzer to trigger on combinations of pin 4 and 5 as CS or just pin 5 as  CS that seem to be always 0 when trasnfers are made.

And now get us some nice decoded data, my better half is calling for lunch, but I'll be back.
   
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Yansi on January 01, 2018, 12:28:27 pm
Those scope measurements look bad. You need to use better probing technique. Use very very short ground lead or make a 50ohm cable terminated properly at both ends.  Otherwise the waveforms will be full of crud. Probing high speed digital circuits ain't no easy...
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Chris56000 on January 01, 2018, 12:33:37 pm
Hi!

One of these is within my monthly pocket money allowance – would it be worthwhile trying one on the FY6600?

https://m.ebay.co.uk/itm/USB-Logic-100MHz-16Ch-Logic-Analyzer-16-Channel-Analyzer-for-ARM-FPGA/182821963784?epid=915703876&hash=item2a9109c808:g:OdwAAOSwLiJZ3YiF

Chris Williams
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 01, 2018, 12:51:19 pm
Hi!

One of these is within my monthly pocket money allowance – would it be worthwhile trying one on the FY6600?

https://m.ebay.co.uk/itm/USB-Logic-100MHz-16Ch-Logic-Analyzer-16-Channel-Analyzer-for-ARM-FPGA/182821963784?epid=915703876&hash=item2a9109c808:g:OdwAAOSwLiJZ3YiF

Chris Williams

From the Chinglish description it sounds OK, especially if it's supporting the original software somehow.

@Yansi: I double dare you to get better waveforms with this POS TBS1104 !!!
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: g0mgx on January 01, 2018, 12:51:43 pm
I'm off to do some more research into this data format.

(http://qsl.net/g/g0mgx//BlogFiles/FeelTech/Pulse%20View%202.png)

Mark
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 01, 2018, 12:56:53 pm
I'm off to do some more research into this data format.


Mark

Mark, the pin 6 clock looks a bit strange to me, there should be 16 clock cycles and they are not, at least in the picture, can you switch your LA to state mode and sampe using pin 6 as clock ?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: g0mgx on January 01, 2018, 01:19:49 pm
Interesting

I can see and count 16 clock cycles on the 'scope but not on the LA.

I've just hooked the LA directly to my sig gen and it's good up to about 3MHz and then the capture becomes inaccurate above that.

Therefore this LA of mine is a load of https://www.urbandictionary.com/define.php?term=Dingo%27s%20Kidneys (https://www.urbandictionary.com/define.php?term=Dingo%27s%20Kidneys)

Mark
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 01, 2018, 01:22:46 pm
Yup, dingo kidney it is, same as my 4 channel scope  :rant:, but hopefully in state mode it will be able to clock with 18MHz, if not, you can safely discard it.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: g0mgx on January 01, 2018, 01:34:12 pm
I think it is related to USB connection speed so have some things to try.

Mark
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 01, 2018, 01:51:53 pm
Yup, if the LA doesn't have a lot of local buffers, the samples will be lost in unattended sampling.
Better switch it to state mode and use SPI_SCK (pin 6) as sampling clock, at least the data will be correct.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Chris56000 on January 01, 2018, 03:46:19 pm
Hi!

Quote
From the Chinglish description it sounds OK, especially if it's supporting the original software somehow.

Fair enough - I'll try one and post what I get on here using it when it arrives!

Chris Willams
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: g0mgx on January 01, 2018, 05:03:56 pm
Better switch it to state mode and use SPI_SCK (pin 6) as sampling clock, at least the data will be correct.

I dont see any reference to "state mode" in PulseView - might it be called something else?

Installing a USB3 PCI card has improved things, but still I am missing samples at very repeatable intervals - looks like something else is occupying the PC at those times as the pulses being dropped now are evenly spaced. It is supposed to support up to 24MHz dependent on PC hardware and data transfer rates so there are more options for me to try.

I haven't given up yet (well not quite anyhow).

Mark
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 01, 2018, 05:17:40 pm
Hi!

One of these is within my monthly pocket money allowance – would it be worthwhile trying one on the FY6600?

https://m.ebay.co.uk/itm/USB-Logic-100MHz-16Ch-Logic-Analyzer-16-Channel-Analyzer-for-ARM-FPGA/182821963784?epid=915703876&hash=item2a9109c808:g:OdwAAOSwLiJZ3YiF

Chris Williams

From the Chinglish description it sounds OK, especially if it's supporting the original software somehow.


Those are blatant copies of a Saleae product which sells for a lot more and of very high quality.  I've not investigated closely, but I *think* that Saleae has the source code available online.  It appears that their attitude is we're selling quality hardware at a fair price.  You can buy cheap knockoffs and use our software if you want.  When you get tired of the problems you'll want to buy one of ours.  It also works with Sigrok.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 01, 2018, 06:43:13 pm
Better switch it to state mode and use SPI_SCK (pin 6) as sampling clock, at least the data will be correct.

I dont see any reference to "state mode" in PulseView - might it be called something else?

Installing a USB3 PCI card has improved things, but still I am missing samples at very repeatable intervals - looks like something else is occupying the PC at those times as the pulses being dropped now are evenly spaced. It is supposed to support up to 24MHz dependent on PC hardware and data transfer rates so there are more options for me to try.

I haven't given up yet (well not quite anyhow).

Mark

OK, I had a look on this PulseView software, same unintuitive, clumsy interface (but hey, it's scriptable) and a complete lack of documentation, so to say a typical open source project.
So to summarize, your problem is that blindly sampling at the highest speed will not give anything anything besides digital garbage, because the you can't stream fast enough over USB at this clock.
So forget about it and don't do it anymore, it's useless.


Good, now from what I've seen from the abstraction aspies that build that clumsy unintuitive junk decided that the distinction between sample and state mode is not necessary (HP, Agilent and friends must be cretins to do it  :palm:) so no mention about it, BUUUT it seems that you can assign a signal to be used as a state clock, of course I had to google this, because it's not obvious.
So assign the Pin6 as the (state) clock and you should be able to collect some meaningful data, I would sample at rising edge.
Basically this way you just record the states and bits that are necessary and don't play an oscilloscope when it's not needed, the sampling feature is cool in many situations but not in this case.
If even after assigning the external clock, the LA can't save correctly over an USB 2.0 the short and anemic bitstream, then either throw away the hw or the sw.
Good luck and bring us some data to chew on  ;D
   
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cpposteve on January 01, 2018, 07:03:21 pm
Partner bought me one of these for christmas as im currently trying to self teach my self electronics (have been for the past 20+ years) and looks to be ok for the beginner, was just wondering to myself today if there is any firmware updates for this, and a few seconds on google brings me this  :'(. anyway, really interesting reading this thread and to all those that are helping to get to the bottom of this keep up the good work.

steve
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 01, 2018, 07:32:18 pm
Partner bought me one of these for christmas as im currently trying to self teach my self electronics (have been for the past 20+ years) and looks to be ok for the beginner, was just wondering to myself today if there is any firmware updates for this, and a few seconds on google brings me this  :'(. anyway, really interesting reading this thread and to all those that are helping to get to the bottom of this keep up the good work.

steve

Hi Steve and welcome to our merry gang  ;D, be yourself the change in the firmware, and if you want to train yourself in electronics (the practical side) now it's an excellent change to do it, select from the plate of goodies:

- Look higher in thread, practical examples on how to make the device electrical safe for other devices, replacing the power connector with a grounded one, changing the cabling and modifying the back pannel.
Skills needed: basic craftsmanship with a Dremmel tool and a file, some basic soldering skill, ability to follow simple instructions and pictures.

- Capture the schematic of the Power Supply (low skill), Front Panel (average skill) and Signal Board (advanced skill).
Skills needed: The ability to disassemble non-destructively an equipment, recognizing components, using a multimeter with a continuity beeper, using a schematic capture CAD program ( KiCAD, Circuit MAker, pirated version of Altium).

- Replace the miserable 16V electrolytic capacitors on +/- 12V rails in preparation for changing the power supply to a better one delivering stabilized +/- 15V.
Skills needed: Basic desoldering/soldering skill, a good soldering station and eventually a desoldering tool.

- Help the effort of decoding the communication protocol between the FB and SB, to be able to control the device with another software or board, for example an RPi. Also if the FW craps out, to get your calibration constants in a safe place.
Skills needed: Ability to work with a scope and logic analyzer, connecting over the signal cable in a movie hacke way :). Tools needed: a GOOD logic analyzer and a reasonable scope (this will be needed later).

- Help build a new, improved firmware for the front panel or for other MCU with a LCD, alternatively for a tablet, Android or IPAD
Skills needed: understanding the hardware and the control protocol, advanced programming capabilities for iOS or Android.

- Improve the Signal Board and signal quality, replace the power supply with a better one with stabilized outputs, eventually a linear one instead of the switching mode one, replace the output operational amplifiers, recalibrate the whole system while system while doing many measurements for at least 1024 calibration points, enter in flame fests about the spectrum analyzer settings and rubidium controlled reference clocks.
Skills needed: master analogue and digital hacker skills. Tools needed: Highly advanced Spectrum analyzer, GPS synchronized frequency reference, complex power meters with precise probes, highly advanced scope to measure the phase shift.

- Rebuild the FPGA programming based on the above acquired knowledge, discover neat trick to move the frequency for non sinus waveforms, shame the FeelTech Chinese programmers and become a forum luminary and mentor. Avoid and be anoyed about all the recruiters begging to hire you.
Skills needed: alpha level hacker in mixed mode devices. Serious deep theoretical and practical knowledge of the whole matter. Tools needed: cheap USB Blaster-2 and Quartus software over what you've aleady collected.

So you see that starting with this humble cheap generator can improve your electronics skill and advance you professionally a lot. You just have to start  :D, so go get'em  :box:
 
 
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Chris56000 on January 01, 2018, 08:31:12 pm
Hi!

Quote
Hi Steve and welcome to our merry gang  ;D, be yourself the change in the firmware, and if you want to train yourself in electronics (the practical side) now it's an excellent change to do it, select from the plate of goodies:

- Look higher in thread, practical examples on how to make the device electrical safe for other devices, replacing the power connector with a grounded one, changing the cabling and modifying the back pannel.
Skills needed: basic craftsmanship with a Dremmel tool and a file, some basic soldering skill, ability to follow simple instructions and pictures.

- Capture the schematic of the Power Supply (low skill), Front Panel (average skill) and Signal Board (advanced skill).
Skills needed: The ability to disassemble non-destructively an equipment, recognizing components, using a multimeter with a continuity beeper, using a schematic capture CAD program ( KiCAD, Circuit MAker, pirated version of Altium).

- Replace the miserable 16V electrolytic capacitors on +/- 12V rails in preparation for changing the power supply to a better one delivering stabilized +/- 15V.
Skills needed: Basic desoldering/soldering skill, a good soldering station and eventually a desoldering tool.

- Help the effort of decoding the communication protocol between the FB and SB, to be able to control the device with another software or board, for example an RPi. Also if the FW craps out, to get your calibration constants in a safe place.
Skills needed: Ability to work with a scope and logic analyzer, connecting over the signal cable in a movie hacke way :). Tools needed: a GOOD logic analyzer and a reasonable scope (this will be needed later).

- Help build a new, improved firmware for the front panel or for other MCU with a LCD, alternatively for a tablet, Android or IPAD
Skills needed: understanding the hardware and the control protocol, advanced programming capabilities for iOS or Android.

- Improve the Signal Board and signal quality, replace the power supply with a better one with stabilized outputs, eventually a linear one instead of the switching mode one, replace the output operational amplifiers, recalibrate the whole system while system while doing many measurements for at least 1024 calibration points, enter in flame fests about the spectrum analyzer settings and rubidium controlled reference clocks.
Skills needed: master analogue and digital hacker skills. Tools needed: Highly advanced Spectrum analyzer, GPS synchronized frequency reference, complex power meters with precise probes, highly advanced scope to measure the phase shift.

- Rebuild the FPGA programming based on the above acquired knowledge, discover neat trick to move the frequency for non sinus waveforms, shame the FeelTech Chinese programmers and become a forum luminary and mentor. Avoid and be anoyed about all the recruiters begging to hire you.
Skills needed: alpha level hacker in mixed mode devices. Serious deep theoretical and practical knowledge of the whole matter. Tools needed: cheap USB Blaster-2 and Quartus software over what you've aleady collected.

So you see that starting with this humble cheap generator can improve your electronics skill and advance you professionally a lot. You just have to start   :D, so go get'em  :box:

Amen to that – that's basically my plan with these (at least as far as the first five paragraphs at any rate!) as well!!!!

Chris Williams
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 01, 2018, 10:56:43 pm
If you've got some spare time after what @DC1MC has outlined you can help with this project:

https://www.eevblog.com/forum/testgear/gw-instek-gds-2000e-released/msg1388999/#msg1388999 (https://www.eevblog.com/forum/testgear/gw-instek-gds-2000e-released/msg1388999/#msg1388999)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on January 02, 2018, 09:45:22 pm
Hi

You know what ? I'am a happy man  :-+
All the modifications I intended to do since the FY6600 arrived here are now completed.

- Mains socket with earth tied to ground : done
- Internal PS upgrade with fast switching diodes, better output capacitors : done
- <1ppm clock (low cost DIY 50MHz) : done
- reflashing the flash memory where the sine waveform had been corrupted : done

Flashing : thanks to Cybermaus for his precious tips.
One more advice, don't forget to firstly erase the flash before rewriting it !
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 02, 2018, 10:11:55 pm
Hi Ebel, nice mods, I plan to do them myself after I'm done with the "hacking", if the device survives ;).

Would you join our reversing effort for the protocol ?

 Cheers,
 DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 02, 2018, 11:03:19 pm

- reflashing the flash memory where the sine waveform had been corrupted : done

Flashing : thanks to Cybermaus for his precious tips.
One more advice, don't forget to firstly erase the flash before rewriting it !

How?  Please tell us!!  I've been waiting 2 weeks for FeelTech & sportgogo to reply with anything more than empty promises.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 02, 2018, 11:15:03 pm

- reflashing the flash memory where the sine waveform had been corrupted : done

Flashing : thanks to Cybermaus for his precious tips.
One more advice, don't forget to firstly erase the flash before rewriting it !

How?  Please tell us!!  I've been waiting 2 weeks for FeelTech & sportgogo to reply with anything more than empty promises.

It's the Signal Board flash where the waveforms are stored, the Front Panel firmware still has to be "liberated" ;)
 
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DaveR on January 02, 2018, 11:47:29 pm
Hi Everyone - another new member here.

I've been reading this thread for a couple of weeks, and my FY6600 just arrived today.  I've only had half an hour to play with it, and it seems to be working fine.  I've also had a look inside in preparation for doing the PS mods, and the main board is now up to v1.501.  The PS board is one made by Suoer, and looks even weedier than the Feeltech board in other members' boxes (but has the same layout).  It's giving 4.33uA @ 92.4v AC on the BNC sockets, so the earth mod is a prority.

I also thought I'd take a look at the stuff on the CD to see what version the software was up to (only 5.2), and went to check the version I downloaded and installed from the Feeltech website a few days ago, using the customary Help - About route.  However, on this version (5.3 as I found out from the original filename), there is no "About", but a single menu option under Help, labelled "Repair_Sine", which attempts to connect to the FY6600 when clicked.  As I haven't connected the unit to my PC yet (and won't be until the mods are done) I have no idea what the outcome would have been, but what's the likelihood of Feeltech having included an undocumented fix for the corrupted sine waves problem in their latest PC control software?  Just a thought ...

Regards,
Dave
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: g0mgx on January 03, 2018, 08:30:08 am
Hi Dave

Interesting!

When you say your unit is working - are you able to reproduce any of the issues in my video?

http://g0mgx.blogspot.co.uk/2017/12/feeltech-6600-issues-list.html (http://g0mgx.blogspot.co.uk/2017/12/feeltech-6600-issues-list.html)

Assuming your version of firmware is the same as mine, if your unit doesnt exhibit the same issues as mine, then I will have to start to look at other possible hardware issues in my unit.

Grateful for your report back!

Mark
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DaveR on January 03, 2018, 11:40:52 am
Hi Mark,

I'll see if I get time later today to do a comparison, but right now the DPD man has just been to the door and I've got a nice new Airspy HF+ in my hand which needs to be played with!

Regards,
Dave
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: plb on January 03, 2018, 11:48:10 am
I have been following this thread for some time. I am not in the same league as you hackers, but your discussion has inspired me to look into logic analysers. My el cheapo unit arrives in a couple of days. I have downloaded the Seleae software and played with it in demo mode, but I'd rather use Sigrok because of the open source licence and the possible proprietory blocks I will find in the Seleae. I have explored the Sigrok site but find I don't speak the language. Trying to download Pulseview sends me around endless loops and null files. Can anybody list how to download and install Pulseview for Windows 10? I'd appreciate the help. Thanks.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 03, 2018, 11:52:45 am
@plb - And I thought that down there they speak a dialect of English  >:D

Here:
https://sigrok.org/wiki/Downloads (https://sigrok.org/wiki/Downloads)

Direct links:
http://sigrok.org/jenkins/job/sigrok-cross-mingw/buildtype=static,debugtype=release,platform=cross-i686-w64-mingw32/lastSuccessfulBuild/artifact/pulseview-NIGHTLY-32bit-static-release-installer.exe (http://sigrok.org/jenkins/job/sigrok-cross-mingw/buildtype=static,debugtype=release,platform=cross-i686-w64-mingw32/lastSuccessfulBuild/artifact/pulseview-NIGHTLY-32bit-static-release-installer.exe)

But IMHO, the software is crap.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on January 03, 2018, 08:12:45 pm
Would you join our reversing effort for the protocol ?

 Cheers,
 DC1MC

Could be a nice challenge, thank you for the invitation.
however that was not my trip when I bought the FY6600 and I've no skills in hacking protocols (nor the set of equipment to do that).
My generator woks fine now after beiing modified as described above.
Go ahead DC1MC, I'm with you  ;)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on January 03, 2018, 08:44:23 pm

- reflashing the flash memory where the sine waveform had been corrupted : done

Flashing : thanks to Cybermaus for his precious tips.
One more advice, don't forget to firstly erase the flash before rewriting it !

How?  Please tell us!!  I've been waiting 2 weeks for FeelTech & sportgogo to reply with anything more than empty promises.

Have a look at this post, you'll have all the explanation to read/write the flash memory.
https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1352448/#msg1352448 (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1352448/#msg1352448)
All you need is a CH341a board (seek it on ebayy or aliexprss, mine is the black board), and some skills in cabling for linking the JTAG footprint on the FY6600 main board to the CH341.

FY6600    CH341(25SPI pins)
1   ->       6
2   ->       4
3

4  -> I
5       I (connect JTAG 4 to JTAG 6 to disable the Cyclone during flash read/write operation)
6  <- I

7   ->    2
8   ->    1
9   ->    5
10 ->    4 (same as 2 = GND)

CH341A = set to Windbond W25Q16BV
If your cabling is correct you'll be able to read the flash memory.
Let us know ;-)


Cheers
(don't hesitate to DM me if you need some help)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DaveR on January 03, 2018, 09:15:34 pm
Hi Mark,

I've watched your video and tried to replicate the issues you noted, but with limited success.  I have no problem at all with Ch2 switching on after a soft off and on, and no problems with remembered offsets, regardless of waveform, frequency or amplitude set. (I assume you've checked the channel boot conditions [SYS - F4] to make sure that Ch2 is actually set to turn on?)  I did get the apparent amplitude jump when changing from 0.5v to 0.6V, but it's caused by an offset of 18-20mV occurring when the relay activates - the amplitude changes correctly, but the whole waveform moves vertically, and this can be seen in the video as well.  Obviously the circuits switched by the relay are not as well matched at the changeover as they could be.  The relays in mine also change with just a single click, so you could be right about a dodgy one in yours (or maybe a borderline voltage failing to activate it cleanly?).

You mentioned a phase change problem at one point, but all I could find was little glitch which occurred when changing amplitude on Ch2 at 10MHz whilst the scope was set to trigger on Ch1 - when the relay activated as above there was a slight (12deg) phase shift.  This wasn't present at much lower frequencies, so it's probably only noticeable at the higher end of the scale, and it disappeared when I set the scope to trigger on Ch2.

I hope this is of some use!

Regards,
Dave
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Chris56000 on January 04, 2018, 07:06:13 pm
Hi!

My FY6600 60 MHz unit arrived this morning, in a plain cardboard box with "FY6600 signal Generator" in black on the side.

Supplied with the generator is -

"QA Assurance" card entirely in Chinese;

A thin floppy BNC – BNC lead about 30 cm long;

One (not two!) BNC – Crocodile–clip lead;

Software CD that might or might not be readable;

Unbranded "Figure–of–8" lead; (I thought Feel–Tech promised they'd fit a three–pole connector?! Or have we to wait for the delights (!!!!) of the next model?!)

Piccies to follow tomorrow when I've brought it home! I'm not sure what version F.W. they've foisted on me as I've not tried it out yet!

I'll begin with measuring the phantom BNC–common to mains earth voltage and the maximum p–p  square–wave amplitude and frequency before serious distortion begins, and also the PSU voltages etc.

I realize this is completely standard stuff others have already done, the idea being to give a comparison between older and more recently supplied units, as other Members have found the internal cheap power–supply boards fitted are subject to considerable variation in type and performance!

I propose to use the AliExpress/Bangoood USB Multi–Output Kit PSU (300 mA nom. per o/p., plus one of the "LM317/LM337 Linear Voltage Regulator Kits" to replace the low quality original, the linear kit carrying the rectifiers, etc., used to give ± 15V for the output–amplifiers, whilst the +3.3V and 5V outputs from the "Banggood" kit will supply the digital sections. A toroidial 18V 1A mains transformer is proposed to supply the replacement PSU PCBs and full documentation/pictures will be provided for this.

As well as the above, I'll convert the mains switch to illuminated D.P. rocker as recommended by Elektor magazine in their guide "Safety Recommendations for construction of Electronic Equipment", frequently republished in their magazine.

I'll start work on the front–panel schematic & parts–list next week!

Chris Williams
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 04, 2018, 07:25:33 pm
My Intronix LogicPort arrived today  8), I'll familiarize myself with the software and tomorrow I'll do a decoding session.  :box:
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Studio1@29 on January 05, 2018, 12:13:28 pm
I have just taken delivery of a FeelTech FY3200S  Dual Channel Arbitrary Function Signal Generator/Counter from e-Bay and it cost  £46.99 (inc delivery) It came with a micro CD with User Manual on it - but that was pretty useless given the complexity of this beast - so I e-Mailed the FeelTech Technical Support this morning - and about an hour later got their comprehensive and helpful reply. e-mail: <feeltech@125.com>  Michael  UK
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 09, 2018, 07:56:10 pm
Interesting that FeelTech now has an additional contact.  I've still received *nothing* for either FeelTech or sportgogo.  No replacement panel or firmware update.  Not even an email update on status.

Has anyone with defective FW had any useful response or just lots of empty promises?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Marco on January 09, 2018, 08:22:16 pm
Realistically there's two things they can do :

- Fuck the buyers of 3.0/3.1 firmware devices.
- Provide unprotected firmware we can burn into a new microcontroller ourselves, not ideal but better than nothing.

Anything else costs too much money, given the thin margins. I don't think they should be rewarded for fucking people ... so I think discussion of purchasing/improving the device is undesirable. Hell if I had my way the title would be changed to "FeelTech FY6600, firmware broke, devices bricked, no fix in sight". Use the little power this forum has for the best.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on January 09, 2018, 09:05:43 pm

- reflashing the flash memory where the sine waveform had been corrupted : done

Flashing : thanks to Cybermaus for his precious tips.
One more advice, don't forget to firstly erase the flash before rewriting it !

How?  Please tell us!!  I've been waiting 2 weeks for FeelTech & sportgogo to reply with anything more than empty promises.

Have a look at this post, you'll have all the explanation to read/write the flash memory.
https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1352448/#msg1352448 (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1352448/#msg1352448)
All you need is a CH341a board (seek it on ebayy or aliexprss, mine is the black board), and some skills in cabling for linking the JTAG footprint on the FY6600 main board to the CH341.

FY6600    CH341(25SPI pins)
1   ->       6
2   ->       4
3

4  -> I
5       I (connect JTAG 4 to JTAG 6 to disable the Cyclone during flash read/write operation)
6  <- I

7   ->    2
8   ->    1
9   ->    5
10 ->    4 (same as 2 = GND)

CH341A = set to Windbond W25Q16BV
If your cabling is correct you'll be able to read the flash memory.
Let us know ;-)


Cheers
(don't hesitate to DM me if you need some help)

Hi Ebel0410, rhd. Sorry, was out for a few weeks.

Indeed, Winbond flash has only the waveforms. Enough for Ebel0410's specific problem, possibly/probably not enough for the more generic screen corruption problem.
One warning, with a link that I also added to the original post (https://www.eevblog.com/forum/repair/ch341a-serial-memory-programmer-power-supply-fix/) of the winbond flash: ensure you have a CH341 that can do 3.3V. Some cheap CH341 cannot do 3.3V
The winbond chip can easily deal with 5V, but the FPGA manual is full with warnings about never putting more then 3.3V on its pins.

Unless of course if Ebel0410 already used a 5V CH341. If thats the case, maybe the warning is not so urgent, but I still advise caution.




Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on January 09, 2018, 09:32:05 pm
Hi Dave

Interesting!

When you say your unit is working - are you able to reproduce any of the issues in my video?

http://g0mgx.blogspot.co.uk/2017/12/feeltech-6600-issues-list.html (http://g0mgx.blogspot.co.uk/2017/12/feeltech-6600-issues-list.html)

Assuming your version of firmware is the same as mine, if your unit doesnt exhibit the same issues as mine, then I will have to start to look at other possible hardware issues in my unit.

Grateful for your report back!

Mark

I also do not see those errors with DC offset nor that intermittent amplitude problem.
A broken relay does sound plausible, especially in view of the intermittent nature of it.
Though it would not explain the CH2 not starting up. Did you try unsetting and resetting the CH2 autostart in the system settings?

I did see a phase offset (as well as jitter) at higher frequencies, caused by the 4ns clock cycle.
Originally I explained it  here.  (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1335080/#msg1335080)

At the time I thought it inevitable due to the 250MHz DAC, but later I realized the jitter may be inevitable (or very hard to work around), but since each channel has its own DAC, the 4ns phase difference is just due to sloppy programming.





Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Chris56000 on January 10, 2018, 12:24:59 am
Hi!

My unit arrived with F.W. 3.2, so hopefully no screen–corruption issue!

The mini–CD came with one solitary folder that was named "V6.60" but I couldn't read anything from it!

I've started work on the Front Panel Schematics, they'll be drawn with Abacom's sPlan as I find this quick and easy to use, gives clear results with IEC 60617 symbols, and it's very well suited to front special symbols, lines, etc., etc., to clarify points on a large diagram, which most other tools are incapable of!

There is a free viewer–tool for these but diagrams will be issued in pdf for everyone to be able to read!

Chris Williams
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 10, 2018, 07:42:19 am
Hello everybody, I'm not gone, just finished the vacation and started the work, as usual in the beginning lots of stress and things to catch on  :palm:.

In this WE I'll sniff the hell out of the bus, as promised, I've prepared a special laptop with Win7-32bit for the LA and other 'doze only programs.

Owners of the devices with 3.0/3.1 firmware, especially modified ones without chance for warranty and returns, please also contribute a bit, there is not a big deal to do.

Once I'll get a fairly comlete understanding of the communication protocol, I'll try the Fraunhofer experiment on the FP, just for giggles, unfortunately I only have 3.1 as well, after all the lengthy communication and crap the vendor went fully silent, I can still return the device but why bother, I'll give him a very bad review and they will spring immediately back with a request for modification and hopefully 20EUR back.

 Cheers,
 DC1MC
 
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Chris56000 on January 10, 2018, 02:01:42 pm
Hi!

Let's get that special thread started on FeelTech after–sales support!

There is absolutely no excuse for releasing gear with buggy/known defective firmware onto any T & M market, even a hobbyist one!!

These generators are sold specifically for those who are unable to afford the highest–quality Keysight/Tek/Siglent or Rigol models, and they are entitled to a working instrument that remains so for a reasonable length of time, not half-a–dozen power cycles or so, and expecting users to pay for shipping corrupted units to China, etc., at enormous expense when their export shipments are heavily subsided or free is totally unacceptable!

I am going to put my efforts into the best quality schematics I can provide, plus a pcb design for a combined linear/switch mode PSU, transformer operated, that I will try and make to the same dimensions as the cheap and nasty PSU they came with!

The design will use parts from the Banggood Multi–Output USB power–supply kit for the +3.3 V and the + 5V digital supply rails, plus parts from the Banggood LM317/LM337 Linear PSU Kit for the two ± 15V and + 12V rails for the linear/output parts of the circuit.

NB!!

I'm still waiting for my PSU kits to arrive and I'll need 'em "in the flesh" as it were before I can begin my PSU board design.

The design'll be done in Sprint Layout 6.0 with native and Gerber files supplied, and posted in the Projects thread separately for other Members to study and comment on as needed!

The point being tho, why should all this have been needed in the first place?

Chris Williams
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 10, 2018, 06:55:54 pm
Great spirits think the same, I've bought from fleabay this beauty for 4,5EUR + shipping. Fused and a lot better islated.
The analogue PSU is next on to do list after the whole fw stuff is done.

And it is needed because our Chinese overlords love to keep us occupied with stuff to repair  :-DD.

 Cheers,
 DC1MC


Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DaveR on January 10, 2018, 10:57:50 pm
I've been having a little play with mine this afternoon as well, starting with a switched 3-pin socket on the backplate and earthing the boards.  I still haven't decided what to do about the PS yet, but I checked the output voltages on the weedy Suoer one it came with: +/- 21v and an unstable 4.90-5.10v under no load, dropping to +13.06, -12.10 and 4.97 after boot up, with a 20v PP sine wave output, so not as bad as first feared.

I also wanted to see what it was like if fed from an external wall wart, so I used a 12v 1A supply into a splitter cable feeding a multi output board for the +/-12v lines (as per Diablo's photo - I already had three of these and had planned to try one anyway) and an adjustable LM317 module for the 5v line.  The combination was fine, so is perfectly viable for anyone wanting to run the device in floating mode.  The multi output board couldn't supply enough 5v current to be used by itself, though, as the resettable fuse cut out each time as soon as the FY6600 had booted up.  I think the stated 300mA per line output given in the sales description is rather on the hopeful side, but there's certainly no problem supplying the +/-12v requirements, and nothing on the multi-board even got warm when the LM317 module was used for 5v.  The 1A wall wart was also more than adequate, and was barely warm after an hour's use.

Back on mains power, I checked the frequency accuracy using a 3GHz counter, cross checked with the oscilloscope, and got quite a tight average -4.65ppm result from 0.1 - 60MHz, against the specified +/-20ppm, so I'm not sure whether it's worth the effort to try to improve on that.  I think I can live with making an arithmetic adjustment to set the dialled in value if I ever need super accuracy (which isn't likely).

I also checked for phase shift again, using a constant 5v amplitude, and found that the two channels were only 1.4nS apart after going from 1MHz to 60MHz, although both had also shifted another 2nS along the time axis.  I haven't read your explanation of the 4nS discrepancy you found, Chris, but my readings indicate that it might just be a bit of "natural variation" (in a sample size of two).

Back to pondering what more to do (if anything) with the PS in mine now ......

Regards,
Dave
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Vytautas on January 11, 2018, 01:16:04 pm
Hi, everyone,

Has anybody addressed or figured out the reason (or reasons) for the jitter (for example, about 4 ns jittering on the falling edge of the squarewave) in this unit? Has anybody suggested any solutions yet? I suppose, just changing the clock oscillator to an ultra-low jitter type wouldn't help here. Thanks to everybody's input!
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on January 11, 2018, 01:41:53 pm
I also checked for phase shift again, using a constant 5v amplitude, and found that the two channels were only 1.4nS apart after going from 1MHz to 60MHz, although both had also shifted another 2nS along the time axis.  I haven't read your explanation of the 4nS discrepancy you found, Chris, but my readings indicate that it might just be a bit of "natural variation" (in a sample size of two).

Interesting. I wonder if that is something they fixed going from my 3.1 to your 3.2.
Because for me, it is very clear and certain: 4ns timeshift on the phase over the entire frequency range. Which I interpret as always exactly 1 tick too late on the 250MHz DAC clock
Something that probably is fixable, and maybe they did  :)

Though numerically, I wonder where your new 1.4ns value would then come from. Can you test this specifically with some frequencies which are whole divisions of the 250mHz clock. Like 50.00, 41.66, 35.71, 31.25, 27.77, 25.00 MHz
If it does not happen there, I may be able to come up with some technobabble on how aliasing could cause this.


Has anybody addressed or figured out the reason (or reasons) for the jitter (for example, about 4 ns jittering on the falling edge of the squarewave) in this unit? Has anybody suggested any solutions yet? I suppose, just changing the clock oscillator to an ultra-low jitter type wouldn't help here. Thanks to everybody's input!

Yes, I am pretty sure its its due to the 250MHz DAC clock (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1335080/#msg1335080). So each next sample is 4ns apart, and alas they cannot make a wave rise or fall in the middle of that.
So while the 4ns phase difference is avoidable, I suspect the the 4ns jitter is not. At least, not on a AWG generator.
(a PLL generator would of course be able to get a cleaner square wave)

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Mr. Scram on January 11, 2018, 02:21:54 pm
Hi, everyone,

Has anybody addressed or figured out the reason (or reasons) for the jitter (for example, about 4 ns jittering on the falling edge of the squarewave) in this unit? Has anybody suggested any solutions yet? I suppose, just changing the clock oscillator to an ultra-low jitter type wouldn't help here. Thanks to everybody's input!
Isn't that the classic square wave frequency not being divisible by the clock frequency jitter?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Vytautas on January 11, 2018, 07:58:46 pm
Thanks, cybermaus, looks to be just it. Well, you get what you pay for.  :(
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on January 11, 2018, 08:56:21 pm
Not sure I agree to that.

There are some issues with this device, but the 4ns jitter? I strongly suspect that the 10x more expensive equivalent Rigol DG1062Z 60Mhz 2 channel AWG has the same issue.
So we are getting a more then we paid for.

In fact, all of the device is a good deal, with all quirks, even the leaky PSU, if you check price/performance to what said equivalent Rigol would cost.
Only the firmware-self-destruct is below par. So far below par I cannot advise the device till they have a warranty system.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Marco on January 11, 2018, 09:05:38 pm
As I said, what we should be asking for is firmware we can use to fix our devices. It's the most realistic solution.

PS. I still say change the title of this thread to mention bricking to apply a little pressure, it's a top google result for this device, it can help ... or at least provide a tiny bit of retribution. With the single post from the OP it was clearly an advertising post any way, an advertising post for a device which fucked a fair few forum members.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 11, 2018, 09:20:07 pm
I previously suggested a thread entitled "FeelTech FY-6600 Product Support Reviews" with all the empty promises from FeelTech and the sellers posted.

I plan to do this as soon as I have recovered from my bout of flu.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on January 11, 2018, 09:33:59 pm
I don't think we can change the thread title, can we? It was started by a Feeltech marketing shill.
I do not think Dave would change the title for us. Would set a nasty precedent.

It is the first google result though, a new thread would not easily take that over.

Just always make sure the last page has at least one clear statement "do not buy unless feeltech finally gives warranty" message.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 11, 2018, 10:46:55 pm
I just went through a maddening exercise trying to contact Paypal and eBay who clearly don't want to allow you to contact them except by checkbox forms.  It would appear that I shall have to write a paper letter to complain to eBay.

I ordered mine on 20 Nov and first contacted FeelTech on 8 December.  I feel fairly certain that the strategy at FeelTech is to stall the user until the Paypal and EBay protections expire.

In the meantime, I've modified my .sig.  I should like to suggest that others do similarly.  That will spread the word rather widely.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: bitseeker on January 11, 2018, 10:59:52 pm
rhb, yeah, it is buried a bit deeply. However, you can call them by navigating as follows:

1. Go to https://ocsnext.ebay.com/ocs/home
2. Click Contact us button
3. Select Buying
4. Select Returns
5. Select Returning an item
6. At the bottom of the page, click Call us or call me button
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DaveR on January 11, 2018, 11:13:36 pm
Can you test this specifically with some frequencies which are whole divisions of the 250mHz clock. Like 50.00, 41.66, 35.71, 31.25, 27.77, 25.00 MHz

I did the measurements at the requested frequencies, a lot more carefully than the previous day's rough look, and took the average over four separate trials, after a 30 minute warm up period.  The Ch1 trace was centered exactly on the crosshairs at 25MHz, and the Ch2 lag time was measured at each frequency, the results being:

25.00MHZ   1.00nS
27.77MHz   1.00nS
31.25MHZ   1.10nS
35.71MHz   1.00nS
41.66MHz   1.10nS
50.00MHz   1.20nS

In fact, the relative phase shift was constant from at least 5Mhz to 50MHZ, but both traces kick laterally by about 2nS at 20MHz - otherwise their positions are quite stable.

One thing I did notice today, however, is that the Ch2 amplitude is about 0.15v less than Ch1's when set to 5v at 25MHz, when the channels are supposed to be in sync, and the difference appears to get bigger as the frequency increases.  I'll have to have another look at that to see exactly whats going on over the whole range, and see if other waveforms are affected.

Regards,
Dave
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: plb on January 12, 2018, 07:37:55 am
Somewhat unnerving that its labelled as 12v but measuring 15.8V and has 16V rated output caps. They should be 25V rated.

These voltages may well be an issue. Mine are around 14V. The negative 5V regulator gave up the ghost, truncating the negative half of the output waveforms. Both it and the positive 78L05 got stinking hot in operation - I couldn't touch them for more than a few millisec- and the 100uF capacitors got uncomfortably hot. Replaced the negative regulator, then the positive one carked. Its replacement carked, so I mounted a TO220 7805 and ran wires to the SMD pads. Both the regulators are now tolerable to touch. I took the opportunity to replace the metal can caps with 25V tantalum/MnO2 types. They barely get warm. It's been running a couple of hours now. Fingers crossed.

And on another subject - if you ground the signal common, run the 3rd pin ground to the power supply board, not the main board, otherwise when you disconnect the power supply board from the main board it is easy to defibrillate yourself. (Ask me how I know...)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Vytautas on January 12, 2018, 11:24:34 am
Not sure I agree to that.

There are some issues with this device, but the 4ns jitter? I strongly suspect that the 10x more expensive equivalent Rigol DG1062Z 60Mhz 2 channel AWG has the same issue.
So we are getting a more then we paid for.

In fact, all of the device is a good deal, with all quirks, even the leaky PSU, if you check price/performance to what said equivalent Rigol would cost.
Only the firmware-self-destruct is below par. So far below par I cannot advise the device till they have a warranty system.

Sorry. I expressed myself wrong. I meant that for this money you cannot expect it to be perfect. And yes, this generator certainly satisfies my needs. By the way, I replaced the power supply again. Or, rather, the transformers to one torroidal. Voltages are still +-15V. Also, replaced the 16V electrolytics to be sure with 35V ones (not SMD but through-hole ones; just soldered them on top and used some hot glue to fix in place). Now, somehow, the waveforms do not show ANY visible distortion at any settings. Even the slight distortions you saw in my previous post, are gone.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on January 12, 2018, 09:21:41 pm
Can you test this specifically with some frequencies which are whole divisions of the 250mHz clock. Like 50.00, 41.66, 35.71, 31.25, 27.77, 25.00 MHz

I did the measurements at the requested frequencies, a lot more carefully than the previous day's rough look, and took the average over four separate trials, after a 30 minute warm up period.  The Ch1 trace was centered exactly on the crosshairs at 25MHz, and the Ch2 lag time was measured at each frequency, the results being:

25.00MHZ   1.00nS
27.77MHz   1.00nS
31.25MHZ   1.10nS
35.71MHz   1.00nS
41.66MHz   1.10nS
50.00MHz   1.20nS

In fact, the relative phase shift was constant from at least 5Mhz to 50MHZ, but both traces kick laterally by about 2nS at 20MHz - otherwise their positions are quite stable.

One thing I did notice today, however, is that the Ch2 amplitude is about 0.15v less than Ch1's when set to 5v at 25MHz, when the channels are supposed to be in sync, and the difference appears to get bigger as the frequency increases.  I'll have to have another look at that to see exactly whats going on over the whole range, and see if other waveforms are affected.

Regards,
Dave

OK, I have a confession to make.
Just to dot the i's, I figured I also measure the delay on my device for all these frequencies. *and now I measure the same 1.2ns*

So I tried all sorts of things to recreate my original delay of 4ns. Long story short, I think I used cables of different length back then... |O
Sorry

However, the 4ns jitter (and its explanation of 250MHz DAC) stands. Just the phase difference does not, it is 1.2 and not 4 on my V3.1.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DaveR on January 13, 2018, 04:50:31 pm
Yep, different length cables certainly make a difference - even 25mm, as I've just found out, is noticeable when the cables are swapped over.

I've also discovered that the 0.15v amplitude difference I was seeing was caused by the ultra-crappy BNC lead which Feeltech supplied: it's got twice the resistance of an RG58 lead of similar length, and probably a huge impedance difference as well.  The BNC connectors are so loose they won't lock onto the sockets properly, and one of them even pulls straight off!

It's prompted me check all my interconnect leads, and I've discovered that I haven't got a single pair of equal length and made from the same cable and fittings, so that's my next little tasklet for this evening....
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Vytautas on January 13, 2018, 05:51:28 pm
Damn Chinese piece of crap!!!
I was today using the fy6600 for some tasks and all of a sudden here what jumps out. The sine wave goes crazy. It is all over the place (multiple sine waves flashing all around) and the screen of the fy6600 starts showing all kinds of mess. The supply voltages are fine. Output amps seem to work fine, but there is something with the soft, I think. My version is 3.0. Damn Chinese crap. Does anyone have experience of FeelTech responding to these issues?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 13, 2018, 06:02:44 pm
You're done for it, as you can see the<firmware version 3.0 it's a time bomb, and yours just exploded.  :'(
Interested in joining the firmare reversing/extracted effort, because there will not be any trip to China and back for your device ?

 DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 13, 2018, 06:20:04 pm
I found I could use mine by resetting the idiotic values.  IIRC there is an ARB setting with a valid sine wave.  As for the rest, read my .sig :-(
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Vytautas on January 13, 2018, 06:22:04 pm
Sure I am interested.
What a nonsense those guys do not provide any support for soft upgrade!  >:( >:( >:(
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DaveR on January 13, 2018, 10:32:37 pm
Out of curiosity, Vytautas, why don't you give the "Help - Repair_Sine" option in the latest control software a try.  We don't know what it does yet, but my guess it was added in after it became known that 3.0 was a major problem, and this could be the fix for it.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: jleg on January 14, 2018, 09:32:15 am
Out of curiosity, Vytautas, why don't you give the "Help - Repair_Sine" option in the latest control software a try.  We don't know what it does yet, but my guess it was added in after it became known that 3.0 was a major problem, and this could be the fix for it.

No, this unfortunately is not the fix. Not sure, if this even is a fix for anything else...
The only thing  on my V3.0 which remained not being totally scrambled is functionality of channel 2. Since the display still is not of much use though, the PC software helps a bit controling the thing.
And in fact, after applying the „fix sine“ from the menu, also the sine shows up again. But unfortunately, this does not last long, nor does it survive a restart. So you end up applying this again and again...

P.S.: just for completeness - nothing heard back from Feeltech, no proposal or anything.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Vytautas on January 14, 2018, 09:59:29 am
Just tried the "sine repair" thing. Thank you for notifying me.
Unfortunately, that is not repairing anything. Now I can control the sine wave from the PC and it works, when controlled by PC. But the rotary knob does not work for setting the frequency, it only controls the amplitude. The screen still has various signs on it. And other waveforms do not work in any way, neither when controlled from PC.
In a current condition its a 100 euro paper weight.  |O
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on January 15, 2018, 07:39:34 pm
I saw the topic on FY6600 and signed up,

Thanks for all the great tips and suggestions ,

I just ordered one from ebay,

I was thinking ,a neat way to get galvanic isolation without completely replacing the psu with a linear one is to simply add a shaver transformer isolator socket to the enclosure 230/110-230volt ,plenty of room to mount the switch modes along side too .
Costs around 10 euros from my local electrical supplier .
I think two seperate switchmodes is the way to go ,one for the 5 volts and another for the +/- rails .Replacing the no brand psu caps with proper items should help a lot also. Rf and magnetic sheilding of the transformer and switchers might be worth doing as well as some extra LC at the dc outputs .
 


 
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on January 15, 2018, 07:45:04 pm
Common shaver type socket
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on January 15, 2018, 09:23:33 pm
Theres a chunky ground terminal on the transformer ,that could remain permanently bonded to mains earth . A 'system' ground switch could be placed between the ground terminal of the psu and mains earth,that way you decide if you want the unit grounded through the mains line or via the unit under test etc ,it allows ground loops to be  broken if the need arises .

I havent tried feeding a switchmode from a transformer before ,the windings will drastically limit the initial inrush current compared to direct mains connection ,probably no bad thing as the capacitor charge on regular wall warts etc creates quite a spark when they are plugged in ,something Ive never liked about switcher psu's .
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 16, 2018, 01:04:33 am
Why would you order one after reading about the FW issue?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on January 16, 2018, 01:56:08 am
Before I purchased the unit I messaged  the seller asking which firmware revision his units were ,I still havent heard back on it from him .
I went ahead and ordered but told them to hold the order until I get the answer to the question .
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: mr.fabe on January 16, 2018, 02:01:38 am
Before I purchased the unit I messaged  the seller asking which firmware revision his units were ,I still havent heard back on it from him .
I went ahead and ordered but told them to hold the order until I get the answer to the question .
I purchased my unit on Dec 8th and received the 3.2 FW

Sent from my XT1575 using Tapatalk

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on January 16, 2018, 03:07:09 am
Thanks for that Mr Fabe,
Hopefully the bad units have been cleared by now ,the supplier I ordered in from seems to have high volume sales so fingers crossed its all ok at this stage .
I found the op amps for the output stage on ebay too ,so I'll most likely solder a couple of them in while Im at it .
The interest and enthusiasm I found here made me want to buy one ,I can take care of the few fixes like mains isolation , extra power supply capacity and adding the output opamps for about 20 euros in parts so its worth a shot.




Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on January 16, 2018, 05:21:16 am
Touch wood my version 2.9 has been fine apart from the sort out issues earlier this thread. Unless you go over $500 you are still hard pressed to find much if any improvement in features and performance which makes the lack of decent assistance from Feeltech ridiculous as they have a niche they could control.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 16, 2018, 07:41:58 am
In the worst case you get a good FPGA development kit ;).
The probes are set, the sniffing will commence soon !!!
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Vytautas on January 16, 2018, 08:12:44 am
Hi, DC1MC,
please, continue your good project.  :-+
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on January 16, 2018, 10:58:13 pm
I found this and thought it might be of some use ,mentions the Cyclone 4 chip

http://dl.altera.com/?edition=lite (http://dl.altera.com/?edition=lite)

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on January 16, 2018, 11:17:06 pm
Heres a link to a post a while back ,a guy managed to do very similar to whats being attempted here ,

https://www.eevblog.com/forum/testgear/mhs-5200a-serial-protocol-reverse-engineered/ (https://www.eevblog.com/forum/testgear/mhs-5200a-serial-protocol-reverse-engineered/)

maybe its of use .
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 17, 2018, 07:03:10 am
Aaaand just like this the stored sine wave on mine got corrupted ( fw. 3.1), and by just like this I mean changing the frequency and turning on and off the channels !!!
Trully a Piece Of Smart  |O 
I'll continue doing the captures and hope that I'll be able to do a list of commands soon, but owners with fw. 3.1 , you're NOT safe !!!


 DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on January 17, 2018, 09:36:12 am
Well, stored waveform corruption on V3.1 is different then firmware corruption on V3.0
Its probably what this new "Fix Sine" menu option in the PC software is about (do try that) and failing that, you can always rewrite the Winbond flash (or flash section) like Ebel0410 did. (He is the only other person I know about with specific sine corruption, and he also had V3.1)

So it seems indeed V3.1 is not safe, but it is repairable.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on January 17, 2018, 03:19:35 pm
Oh thats bad news Dc ,
Seems crazy that Feeltech wont offer an abillity to upgrade the unit ,anyone that buys this product will have an interest in electronic to begin with ,and getting together the programer card shouldnt be that difficult, it does seem like there might be a few steps in getting the right code to each of the chips ,and the usb connection doesnt seem to be set up to upgrade all  in one go .
It would seem if Feeltech want their customers to remain loyal and not leave them with a paper weight and a bunch of negative press they need to at very least offer people some viable alternative to shipping it back to factory at their own cost.
If Feeltech guys  are steadfastly refusing to offer online updates ,then really they need to start sending out replacement boards to those who can show documentary evidence of these faults free of charge ,really if they just bit the bullet and sent out brand new boxes to its customers who were affected they could probably reverse all the reputational damage that has occured already . Ive just emailed the vendor for the third time asking what software revision the machine they are send me is .this time I reminded him that he simply needs to power up one of the units to check which FW revision its at .For the money Fy6600 is hard to beat in terms of functionality ,if feeltech can fix the issues there onto a winner for sure .
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: jleg on January 17, 2018, 03:32:57 pm
So it seems indeed V3.1 is not safe, but it is repairable.
i would not call this "repairable". It just fixes the issue "for the moment". The next moment, it is gone again. At least this is what i observe with this "repair".
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: CustomEngineerer on January 17, 2018, 04:42:48 pm
It would seem if Feeltech want their customers to remain loyal and not leave them with a paper weight and a bunch of negative press they need to at very least offer people some viable alternative to shipping it back to factory at their own cost.

It would seem that way, but people just keep giving Feeltech their money despite all the negative press that's already out there. Feeltech has made it clear they don't care.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 17, 2018, 09:46:04 pm
Hello everybody, here are some preliminary news on the protocol decoding stuff (btw, the stored sine waves have been repaired):

- The control message that the FP sends seem to be the FULL configuration, that is, the frequency, amplitude and whatever is send for the both channels and the FPGA reconfigures fully.
- The numerical information (at least for the frequency and amplitude) seem to be organized into 48bit !!! numbers ( 3x16bit), there are at least 32 of this 48bit parameters that are send.
- I've managed to identify the frequency slot, it does increase with this stupid mHz increment, and the number reflects the display.
I'm so curios what is happening  if somebody forces a value larger than 60MHz on the slot, especially on the 30MHz units !!!
- I've managed to identify the amplitude slot, this somehow varies monotonic with the display, but there on 1 to 1 correspondence, seem to be some quanta, even values from a table, to be investigated.
- I've managed to quickly reach the limits of the Intronix logic analyzer, to get somehow reliable and repeatable measurements at 18MHz clock, I need to sample at 50MHz and the little buffer fills quickly, even with compression active. the software on the other side was so cool, it took me like 5 seconds change the SPI protocol interpreter from 8 bits to 16bits. I really hope that the owner of the LogicPort IP will produce an updated variant or at least open-source it, because I really like it.
- To continue work I need to use the LA advanced features, like repeated condition trigger, to skip groups of 3 SPI transfers, but that means doing single acquisitions instead of looping and comparing values, and this pisses me off.
!!! WANTED !!! Kind Soul  to Lease a Logic Analyzer  with a RELIABLE sampling mode (3V3 levels) of at least 50MHz (100MHz preferable, not every Chinese firma is Intronix) on at least 4 channels (I need an extra for the extra chip select, to see where this long string of words are going, remember we have 2 chip selects!!!) and yuuuuge buffer, at least 4Msample without compression, there is a large interval in between transfers compared with the actual transfer time of 3 words, and if the LA is of naive design it really needs a large buffer.   

Hopefully I'll be soon able to get the control message, without a powerful LA will be painful, but it's doable.

Humanitarian appeal: Dear gentle beings that lurks on this thread, I know that some of you have these cool scopes with LA and/or preformant LAs, kindly please try to reproduce my measurements, the connector is gigantic at today's standard and there is no pain in hooking the LA, 5 pins with plastic balls it's all that is needed for the grabbers to have a grabbing point ;).
If you don't want, at least some encouraging words will be appreciated  ^-^.

I'm posting some pictures with my setup to encourage you to contribute  :-DMM

 Cheers,
 DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on January 17, 2018, 10:33:14 pm
Hello everybody, here are some preliminary news on the protocol decoding stuff (btw, the stored sine waves have been repaired):
I assume with PC software menu option?

Quote
- The control message that the FP sends seem to be the FULL configuration, that is, the frequency, amplitude and whatever is send for the both channels and the FPGA reconfigures fully.
If it sends the entire config, does that mean the entire waveform gets reset? It seems not. At least not if I change the amplitude (easy to trigger on) on channel A, channel B runs without any discontinuity, and even channel A only changes amplitude while its phase runs continuously.

Image 1: 10KHz + 11KHz and jumping from 4V to 5V
Note: if you change from 5V to 6V, channel A disappears for 4ms due to a relay clicking over

Image 2: same with 1MHz and 1.1MHz
Note that it actually takes 15usec or so for the amplitude to actually rise

That most likely means that the waveform is not reset as the FPGA continues to tick down the waveform samples.
So likely you can expect the same control set for all settings, except when you change the waveform, that will have its own completely distinct control set.

Quote
WANTED !!! Kind Soul  to Lease a Logic Analyzer  with a RELIABLE sampling mode (3V3 levels) of at least 50MHz (100MHz preferable, not every Chinese firma is Intronix) on at least 4 channels.
I assume you mean 'loan'? Sorry, I only have a 20MS/s 256KB Scanalogic-2 (IKALogic)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on January 17, 2018, 11:06:29 pm
I have a MICSIG 1104 on the way (been in this country for 3 days without moving  >:( ) It should be able to cope with the specs you mention and has built in bus decoding installed. Mine is the 30MhZ Signal generator too.

Bus decoding/sniffing isn't my thing but I will try anything 'once'  ;D
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on January 18, 2018, 01:25:23 am
I guess to some extent we all knew what we were getting into buying one of these units ,
Its one of those too good to be true type deals ,but having said that ,for the money involved,for me its worth the risk, I can do all of the upgrades component  wise myself for next to nothing .
Maybe a simple survey in here involving owners of the FY6600 and we could get some stats on the failure rates ,something which Dr Feeltech knows only too well at this stage Id imagine.
Im afraid Im not much use on the programming front ,I can certainly follow instruction on how to flash something but beyond that ,programming isnt my thing .
Analog audio is my main focus,specifically valve/tube gear, the 1's and 0's I dont bother so much with as long as what I put in comes back out cleanly at the other side .

Incidently I went to my electronics recycling point yesterday with a few odds and ends to get rid of ,I took a Technomate sat box back from the heap with me and found a very suitable replacement psu for anything small requireing +3.3+5+12-12 volts inside ,each of the rails has proper CLC filters at the outputs ,something a lot of manufacturers penny pinch over.

Im sceptical of switchmodes because over the years Iv seen some very bizzare behaviour when different units which rely on switcher psu's share a common ground.Once on a live recording session I had a bass player turn up with a Genz Benz ,lightweight 500w amp ,it had an xlr out which I took a connection from to my hardisk recorder/mixer. The amp for what ever reason simply stopped working completely until the signal connection was broken ,accompanied with a mini melt down on behalf of the bass player . Anyway just went back to old fashioned active DI box directly from the bass and everything worked great again , a real ghost in the machine type experience for the amp owner though. Another time I re-jigged a vintage radio cabinet into a modern unit with a switching amp pulled from my fostex PM.03's , it works fine with most sources ,but pair it to a dab radio and the interaction/interference from the two switchmodes makes the whole set up unusable ,a mix of 50/100hz hum and spikey rf voltages are all that come through the speakers ,with very carefull routing of the wiring from the supplies it can work but its well beyond the average persons ability to understand . Id be interested if anyone else has experienced similar weirdness when multiple switchers interact via ground and crap gets induced into your audio wires .

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on January 18, 2018, 02:25:06 am
Forum survey in this case would only reveal a Negative view. We are most likely a few percent of their sales at best and it seems that most have found their way here to improve weaknesses or try and revive dead ones.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on January 18, 2018, 04:38:01 am
I just happened to click on the ebay link that was left by the person who started this post ,
Ironically it says that this sale has been removed by the seller because the item was lost or broken .

You could be right Bean ,maybe a post called 'Feeltech FY6600 Complaints department' for everyone who's been stung might make Dr Feeltech sit up and take notice , aside from a few youtube vids and sellers of the item, google search sends people straight here and it seems to be the only serious blog out there on this particular machine, that gives us a bit of leverage .
Maybe a new topic page where everyone who got a dud FY6600 machine goes and puts the name of the ebay seller, FW version ,and a short description of the fault,nice an simple   ,
Id say it wouldnt take long for Mr Feeltech to hearback from his retailers   :rant:
And that might be enough to change his mind on doing right by the people who were dissapointed , the softly softly approach has been tried, time to up the ante Id say .
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 18, 2018, 07:47:36 am
Quick before going out:
@cybermaus all the measurements were done with the default sine wave on, no custom waveform, too bad about your LA, yes, I wanted to say lease not loan, aber wir schaffen das :).

@beanflying the LA is cool, there is nothing über-hackerish to do, just connect it to the data cable, and write down what get's send when some commands are done. If the LA has a protocol decoder, then there are just a number of values to be jotted down, this will actually be really helpful to be able to compare two separate units.

 Cheers,
 DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on January 18, 2018, 08:25:16 am
Not entirely sure but I think the MICSIG can take videos of the screen  ;D
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on January 18, 2018, 09:15:09 pm
I had been wondering about a question that has arrisen a few times on the thread ,but their didnt seem to be a straight answer to ,
What exactly is the difference between the 15/30/45/60 mhz models , have the upper models the different opp amps on the output stage ,or different power supply ,is there a different software on the higher frequency models or other different hardware modifications ?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on January 19, 2018, 04:07:56 am
Just an introduction today. Feeltech meet MICSIG hardware and software from Shenzen that works  >:D
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 19, 2018, 04:50:38 am
It seems to me that reviewing the other similar units would be more useful for others.  I rather doubt that FeelTech will continue in the T&M business.

It seems to me that the only way to get any kind of warranty out of FeelTech is to order a replacement  from a seller with low cost return shipping. swap the bad board and return for a refund.   However,  a string of V 3.0 or 3.1 units would make even that unattractive.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 19, 2018, 06:56:49 pm
OK gentlemen, the WE is starting and so is the sniffing session.
One thing is for sure, for one click of the encoder in the frequency change mode exactly 17 x 48bit values are send form the FP to the SB.
The frequency value is only linear up to some value, afterwards it become a little strange.
The Intronix LA is really superb, but I've hit as well the limit in the sample memory, what a real pity that the designer got some personality disorder and doesn't want a redesign for a larger sample memory, I will definitely pay for an updated version.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: bsudbrink on January 19, 2018, 07:29:49 pm
Last year, when I decided to by an FY6600, there was a competitor, the JDS6600.  Part of my decision was based on the fact that more people around here seemed more enthusiastic about the FY6600.  I figured, more hacks, more fun.  Thing is, I don't seem to see any further discussion of the JDS6600 past last November.  Does anyone have both?  Does the JDS have similar issues to the FY?  Could the JDS give any clues on how to "get into" the FY?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on January 19, 2018, 08:26:59 pm
The software with the Jds does look better than what comes with the FY6600, maybe its worth trying it out to see if it functions with the Feeltech as well .
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 20, 2018, 12:55:09 am
Unfortunately, there was just enough information to make a bad decision.  I'm considering ordering  either a JDS or Koolertronic unit as a replacement if DC1MC doesn't  manage to document the bus  protocol to the point I can reprogram the FeelTech. Of course, he should return the V 3.1 unit he received as defective and repeat the process until he gets a unit that doesn't crap on itself.

I was visiting my sister in CA and  just got home.  I'm still trying to to get back up to speed with what I was doing when I left.   The migration of my Solaris 10 system from 1 TB to 2 TB disks for the ZFS arrays is almost complete.  So the big project still in progress is the T&M restack.  I've also got to source a distribution  amplifier and set up my Leo Bodnar GPSDO to feed the other instruments.  Which probably won't happen for a day or two as the 40 nS rise time pulse generator is much more interesting. Many years ago I tried to build such a thing and got my head handed to me on a platter.  I plan on a rematch.  I don't intend to try to beat Leo. Just meet my original 900 pS risetime goal set by the Tek 465 cal procedures.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on January 20, 2018, 01:03:59 am
Aside from the software related issues that some have experienced ,the extra features on the FY6600 like sync input ,and the ability to modulate one signal with another just make the FY a better more versatile piece of kit , fingers crossed  the 'Feelers' guys have got their sh1t together with the software glitches now too ,my unit is on the slow boat from China as we speak ,still no response from the seller about which FW version Im getting either , worst comes to worst and they try and pawn me off an older firmware revision I'll most likely shed the load and tell the courier to return it from whence it came. Hopefully  Feeltech have recalled the funky units with FW 3.0 and 3.1 from their retailers at this stage.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 20, 2018, 01:14:44 am
I was told I had a "lifetime" warranty.  FT does not even reply now nor does the seller. sportgogo.  I'm about to start the agony of making formal complaints to eBay and Paypal.

I think that "justice" would be open source FW.  Make it *really* easy to launch a competing product.  Let's face it, there's not a lot to the UI software.  I strongly suspect that the issues result from a demented attitude about "intellectual property".
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on January 20, 2018, 02:27:17 am
I guess we have to clap ourself on the back here in the west ,Im not sure if the concept of intellectual property even existed in China uptill modern times .
Maybe its not just as simple as upgrading the firmware in one go via usb like with most equipment ,maybe the process is fiddly and way to awkward for a non technical person to do .

Thats a real shame they have left you in the lurch RHB, at least you have plenty of documentary evidence from this post to back up your side of the story . I hope you get some satisfaction ,maybe if enough complaints are lodged, Ebay will contact the Feeltech in person for an explanation , at the end of the day the seller is only the middle man and has no control over the quality ,the person who ends up taking the lumps when things go wrong are the actual employees of the seller ,theres a lack of acountabillity from the people raking in the big money ,but isnt that the way all over .

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on January 20, 2018, 07:21:17 am
My opinion of the JDS is it is a rip off of the basic Feeltech unit but they also too some shortcuts and cost savings using a resistor ladder instead of a proper DAC

Just finished a 14 hours day on my feet with another few to clean up yet. Monday/Tuesday I will crack the lid on mine and have a play with the new scope.   :-+
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 20, 2018, 09:14:11 am
Dear forum members, I'm glad to announce the first official results of the FY6600 bus sniffing.

General considerations:
Pinout you can see it on the page 17 of this thread, signal level is 3V3 logic.
The data is transfered form the FP (front panel) to the SB (signal board) and back via 16bit word SPI transfers with an 18MHz clock, MSBit first.
Logically we are talking about a number of 32bit registers, in big-endian format, and one MOSI transfer consists of 16bit register address (so far observed addresses are less than 0x20, but the night is young), followed by the MSW and LSW .

Frequency registers general note:
- There are two 32 bit consecutive address registers for each channel, one holds the frequency in increments of 0.1Hz and the other one the centi-Hz and beyond, going to 0.099999Hz. On my 60MHz unit it goes to the max value and any further attempts to increase the frequency programs the same value. Values are 1to1 linear, no offsets or table lookup found.
The full control message programs 20 x 32bit registers, the register for CH1 are number 9 and 10 in the control message and for CH2 are 11 and 12 (these are positions in the 20 transfers control message starting from 1, NOT the actual register addresses !!!). Order is MSW then LSW, don't know if it matters.
- Frequency setting register addresses:
  CH1 MSW 0x02, LSW 0x01
  CH2 MSW 0x04, LSW 0x03


 >:D note: Is the freq limit hardcoded in the FP (bypassed by a new firmware or MCU), in the SB (bypassed by copying the SB flash) or in the components used (bypassed by soldering the right ones) ?

Next to come: Amplitude

Bonus, for amateur detectives: a Full sine frequency setting message, amplitude is set to 5.0000V, offset 0.00000, duty cycle 50%, phase shift 0.00000.

  8) First prize: The finder of one or the rest registers for setting the amplitude , phase and duty cycle, using just this provided sample.
 :-+ Second prize: The finder of current frequency settings by using the information I've provided.
 >:D Third prize: There is no third prize !!!

Sample (A.M.L):
1D.0000.0002
24.0000.0010
2B.0000.07FF
2C.0000.07FF
06.0000.00C0
06.0000.00C0
2D.0000.0E65
2E.0000.0E65
02.0BEE.32EF
01.0000.AB5C
04.0001.86A0
03.0000.0000
2F.0001.0000
30.0001.0000
05.0000.0000
38.07FF.DFFF
39.07FF.DFFF
08.000F.FFFF
09.000F.FFFF
37.0000.0000


Now  :box:

DC1MC





   

CH
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on January 20, 2018, 10:25:32 am
The unmodified 10KHz of channel B is easy.
The 20.015.998.343.868 uHz on Channel A is also not too hard, but a bit of a random number though.

But is a quiz really the right format to bring us new knowledge. Even if you are in teacher-testing mode, didactically the number set should have been one not obvious from the quiz, but once decoded reward the student with a good feeling. Like 02.075B.CD15 01.0000.04D2 would have. or if thats too obvious, maybe 02.075B.CD08 01.0000.D431

As to the others. Likely this:
The 50% ones are obviously one of the 7FF... values, do not even need a calculator for that. But offset is also a 50% value (0 being the middle)
Of course there are multiple candidates, depending on the resolution I would go for 07FF.DFFF, (not sure about the D) and 0000.07FF for offset.
Phase shift would be one of the 0000 values.


HOWEVER:

If for some technical reason, it was easier to build the FPGA blocks like that, they could just as easily use the 0001.0000 values as a hex 50%, and therefore a full scale would be 0000.0000 to 0001.FFFF to map out the offset. Or the duty cycle.

Or they could use proper binary values, with x0000 being 0, and negative offsets as signed binary, like 0FFFF for -0.001V and x7FFF being the maximum rather then the middle


You see, you are not really playing nice. You had multiple samples, saw what changed when, and know the answers. But now you make the questions as if your answers are the only possible ones, but without extra info, there are multiple solutions.


Anyway, more seriously:
 
>:D note: Is the freq limit hardcoded in the FP (bypassed by a new firmware or MCU), in the SB (bypassed by copying the SB flash) or in the components used (bypassed by soldering the right ones) ?

I would argue (but am not absolutely certain):
- Hardware differences are unlikely due to production cost, cost of keeping multiple stock.
- FPGA is unlikely as it is not protected
- CPU is likely, and in fact the reason why they do not distribute the firmware, even more then them worrying about IP

We can prove the FPGA is not it if someone with a 30MHz V3.1 reads the Winbond, so I can compare with my 60MHz V3.1
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 20, 2018, 10:40:36 am
Oh cybermaus, you hurt me  :P, this is my first capture with the LA, I even forgot what was the idea, prolly to generate a binary pattern of 0x123456789ab.
Besides this I have no clue what other parameter are formated and in which addresses are stored, I'll get them after returning from shopping, now that the other Saturday chores are done.
Parameter settings are easy, but when you press F1 repeatedly, it rereads stuff from the FPGA, I'm really curious what is there.
And of course, Sysinfo decoding it will be interesting.
It really sucks that nobody wants to hook an LA to its unit as well :(, but I will do whatever captures are needed or suggested.
But first parameter settings must be fully determined.
Now Accepting Ideas about some wave forms  to determine the waveform loading procedure!!!

Cheers,
DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on January 20, 2018, 11:07:57 am
Sorry, I did not mean to curb your enthusiasm

Possibly I misinterpreted whether you were quizzing for the duty/offset/phase or did not know yet and was asked us.
But that misunderstanding is then also due to the bringing us the frequency as a quiz. As I said, I do not think quizzing is the way to go here.

The reason I am not LA' ing is multiple:

- I spend a lot of time  learning the STM32 and its features on a blue-pill with the hope of reading it. And I have at this moment confirmed that all the security measures described in the reference manual are in place and working. Many ideas to hack around it came and went out the door again. No closer to reading the FB, but I did spend my time.

- Reading the protocol is interesting, and I am not against puzzles, but it would be only half the work. After that there is also the grinding work of reprogramming another device as UI. Maybe said stm32 blue-pill, but a lot of extra work, and we are bound to also make bugs, like feeltech.

- as stated, my LA is a bit sub-par.

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 20, 2018, 02:55:27 pm
Back from shopping in the most miserable goth-mannheimisch weather evar :(.
So cybermaus, about the the security measures, can you detail, is the MCU closed on level 1 (doable) or on level 2 (not doable) ?
Also there was another kind soul that said he'll work on the FP schematic, any results yet, after the protocol is done I intend to do a Fraunhoffer on the FP, but not before.
In the end, the STM is providing really cool libraries for graphical LCD any many other goodies, it's doable with a bit elbow grease.
Now, enough talkin and more analyzing, up next, output voltage, phase and offset.
DC1MC

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 20, 2018, 04:16:12 pm
- Reading the protocol is interesting, and I am not against puzzles, but it would be only half the work. After that there is also the grinding work of reprogramming another device as UI. Maybe said stm32 blue-pill, but a lot of extra work, and we are bound to also make bugs, like feeltech.

I'm ready to start testing using another device as soon as I have a description of the bus protocol.  I plan to start by using Mecrisp to control the AWG board from a terminal window.  I have an ample supply of dev boards, etc.  This has the major advantage that exhaustive protocol testing is trivially scripted.

I've written thousands of lines of software professionally that were in service for almost 20 years with NO user reported bugs.  This included FORTRAN initializing a function pointer table in C that called FORTRAN routines to populate FORTRAN structures, so not trivial code either.  I realize that is unusual, but it shouldn't be.

@DC1MC Please start a new thread, "FeelTech FY-6600 Firmware Recovery"  in the "Repair" group and put all the information you have  collected in the first post, updated as we collect more information.  That will make it much easier to find out the current status of work.  We should keep the discussion here so as not to clutter up the technical documentation.

I'm still a few days from completing a major workspace  reorganization, but should be in full swing by next weekend at which point I'll start verifying the accumulated documentation. At least in theory I should be able to automate verification using the MSO2204EA features to verify the AWG output for all the bus commands.  It will be an interesting test of the Instek SCPI implementation.

[Edit]  I just saw this.  Never heard of the package, but obviously highly relevant.

https://www.eevblog.com/forum/microcontrollers/truestudio-v9-released-100-free-but-only-for-stm32/?topicseen (https://www.eevblog.com/forum/microcontrollers/truestudio-v9-released-100-free-but-only-for-stm32/?topicseen)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: SMB784 on January 20, 2018, 06:13:33 pm
Perhaps just a general repair thread outlining what steps are necessary to make the power supply safe, ground the device, give it a proper reference, and fix the UI display would be good. Put it all in one place!

Also, my device is also on the slow boat from China, what kind of logistics analyzer is needed to accomplish what's left to do?

i.e. how many channels, what sample rate, and how much sample memory?

If something like this would work, I will spring the cash and join the effort:
https://m.ebay.com/itm/USB-Logic-Analyzer-16CH-100MHz-4CH-400MHz-Base-on-Xilinx-Spartan-6-FPGA-in-US/162474227153?hash=item25d437f5d1:g:3NAAAOSwjyxZcVTv
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on January 20, 2018, 06:26:07 pm
So cybermaus, about the the security measures, can you detail, is the MCU closed on level 1 (doable) or on level 2 (not doable) ?

Short answer: it has RDP1

Longer answer: RDP1 and RDP2 does not exist on the STM32F103C8. Not exact.

You see, the Frauenhofer document is specifically for the STM32F0xx series, which is slightly newer, and indeed have an extra protection option. And because there are 3 protection levels, they call it 0, 1, 2. The older STM32F1xx devices only have RDP, or no RDP (on or off, if you will). No mention of levels anywhere in the document.
But functionally, RDP on is similar to RDP level 1.

That also means that the exact cold-boot race condition that Frauenhofer described, may or may not work.
It is a different device, with a specific implementation change in this specific part of the chip. The flaw was likely also already there in the older series, but we cannot be sure.

I am actually studying the Frauenhofer document at the moment, not merely skimming it an looking at the video, but trying to read and understand every word of it.
But to be honest: Don't hold your breath, I have other stuff to do too.




Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 20, 2018, 09:07:25 pm
Hello again, after a short nap to rest these old eyes, here are some quick answers to the messages until now and some new findings, aka "level control is a new level of...":

@cybermaus: Thanks for clarifying the RDP situation with the FP MCU, I downloaded the code form the Fraunhoffer project, once I have the protocol figured out (in case the firmware/FP dies at least I can control the SB via something else). I wish you'll find some time to contribute further to our little project, but thanks again for all your previous work, it was an inspiration.

@rhb: Your offer to do a detailed and formal protocol testing is wonderful, we need this and we desperately need at least one person with another AWG to do some investigation, as far as I was able to see until now, there are no "secret sauce" calibration values stored somewhere, the firmware trusts the SB to do its stuff, for example, I didn't see so far any difference in setting the amplitude for the channels in the actual firmware, but with your help we can really devise a calibration procedure for the device. Also thanks for the advanced debugger package info, it will come handy later. Finally, I will continue this thread for a while and tomorrow I will start  a new one as suggested.

@SMB784: I will offer some of my findings to kick start your stuff, some are fact(F) and some are anecdotal (A, personal experience):
 - F: As the SPI interface clock is 18MHz, you need an LA that can work reliably at least 100MHz in sample mode.
 - F: The absolute minimum number of channels is 3: CS, CLK and MISO or MOSI, better is 4 (to see simultaneously both data pins) and best is 6, because we have some other signals (an assumed extra CS to select another device, and a "mystery" signal, not determined yet).
 - F: The logic levels are 3V3, single ended, ALL the LA in the world should be able to cope with this.
 - F: The LA has to have some on device memory, either large or with RLL or other compression method, we have some kind of trifecta thing, the data it's very fast when is coming,  but come in widely spaced bursts, and a "naive" LA that once triggered, keeps on sampling, it will need to have a real large sample buffer.
 - F: To add to the sample buffer size, I still have to see how the waveform loading goes over the SPI bus, it could be that my Intronix is insufficient for this.
 - F: The LA should be able to have a reliable 16bit, MSBit first, protocol decoder, or it's useless.
 - A: Personally I use an Intronix LogicPort (one right now on fleabay, https://www.ebay.de/itm/INTRONIX-Logicport-34-Channel-Logic-Analyzer/192427289565 (https://www.ebay.de/itm/INTRONIX-Logicport-34-Channel-Logic-Analyzer/192427289565) ),  and they are still sold, while dated, it does the job (praise benevolent Fraser that offered one at a good price), it has RLL compression and some minuscule sample memory, so while the data can come as it wants, the few Kbits of sample buffer it fills up pretty fast and game over. Buuuut, if one is not lazy and expects the whole control msg in one shot, he can increase the number of trigger condition (CS going down) repetitions and position directly on the needed value or do a multi-segment acquisition. So far it proved to be OK, but I'm shopping for another LA, eventually with USB3 interface, and definitely with a large on device sample memory.
It's a tragedy that the Intronix guy got some kind of brain fart and totally refuses to update the design, he's a very pleasant and helpful person to talk with, UNTIL the design update subject comes :(.
 - A: I was also looking at the DS Xilinx whatever clones, it doesn't seem to have RLL compression implemented, and if so, even with the 256KBits sample memory, it's useless. In streaming mode is definitely useless. But of course, I can only use the seller provided information, that is some distorted chinglish and on 10 similar looking devices you've got 10 different descriptions, they are throwing whatever shit and see which of it sticks on the wall and sells more. And most likely the software is nicely done and a pleasure to work with  >:D.

I have lowered my LA standards as low as possible, but even so, finding a device that has the same features as the Intronix and a bit of extra buffer space under 1000EUR it's just not possible, Chinese or not. And btw, fuck those SA--äE sales drones with a rotating cactus, it took me half an hour with their miserable support software AI or cognitively challenged salesoid to confirm that the latest and grates expensive POS still doesn't have on device memory and doesn't do any RLL compression on acquisition and "it uses the PC memory". Sigh.

As this post has become too long, I will post the amplitude registers and description in my next post (that one will be also long, but with nuuuumeeeers :)

 Cheers,
 DC1MC



 if it's one of these devices that are just some Cypress USB interfaces with some analog front end,


Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on January 20, 2018, 09:31:15 pm
... I downloaded the code form the Fraunhoffer project....

What? Where?
I was under the impression they did not publish the code.

edit: never mind. got it.

Also this is my analysis of the Frauenhofer paper (bad news):

- Cold-Boot SRAM attack: This assumes the bootloader first does a firmware CRC check, so every flash byte passes through the SRAM in an ordered and well-timed fashion. And I think our devices do not do a CRC check. Otherwise, how could they boot up with corrupted firmware

- SWD race attack: Quote: "experiments on a few samples indicate, that other series might not be vulnerable"
Translation: they tried it already on a STM32F1 and could not get it to work (in other places they also refer to F1 by name as "other series")

I am probably going to try anyway...

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: SMB784 on January 20, 2018, 10:08:13 pm
- A: I was also looking at the DS Xilinx whatever clones, it doesn't seem to have RLL compression implemented, and if so, even with the 256KBits sample memory, it's useless. In streaming mode is definitely useless. But of course, I can only use the seller provided information, that is some distorted chinglish and on 10 similar looking devices you've got 10 different descriptions, they are throwing whatever shit and see which of it sticks on the wall and sells more. And most likely the software is nicely done and a pleasure to work with  >:D.

Would it matter if the device has 256 MBits of onboard storage memory, like this one? (https://www.ebay.com/itm/USB-Logic-DSLogic-Analyzer-16Ch-100MHz-4Ch-400MHz-Xilinx-Spartan-6-FPGA/182687940922?_trkparms=aid%3D555018%26algo%3DPL.SIM%26ao%3D2%26asc%3D49899%26meid%3D7312b39552504dc08178c8d5d2f784b7%26pid%3D100890%26rk%3D1%26rkt%3D12%26sd%3D162474227153&_trksid=p2056116.c100890.m2460)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 20, 2018, 11:03:07 pm
- A: I was also looking at the DS Xilinx whatever clones, it doesn't seem to have RLL compression implemented, and if so, even with the 256KBits sample memory, it's useless. In streaming mode is definitely useless. But of course, I can only use the seller provided information, that is some distorted chinglish and on 10 similar looking devices you've got 10 different descriptions, they are throwing whatever shit and see which of it sticks on the wall and sells more. And most likely the software is nicely done and a pleasure to work with  >:D.

Would it matter if the device has 256 MBits of onboard storage memory, like this one? (https://www.ebay.com/itm/USB-Logic-DSLogic-Analyzer-16Ch-100MHz-4Ch-400MHz-Xilinx-Spartan-6-FPGA/182687940922?_trkparms=aid%3D555018%26algo%3DPL.SIM%26ao%3D2%26asc%3D49899%26meid%3D7312b39552504dc08178c8d5d2f784b7%26pid%3D100890%26rk%3D1%26rkt%3D12%26sd%3D162474227153&_trksid=p2056116.c100890.m2460)

Not really 256MBits, the description says:
"DSLogic basic version Specifications:

- Hardware storage:256Kbits"
The ony one that comes close to what I want is/was USBee QX, but they are gone now :(
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 21, 2018, 12:02:06 am
And now the log awaited amplitude settings:

General Notes:
Register addresses:
 CH1 - 0x2D
 CH2 - 0x2E

Range of digital values, both channels, no difference, no channel specific values:
 0x0000..0x0E65 (?!?!)

Ranges and corresponding relay bits in register 0x06 (NOTE the firmware has a naive way to set the register 6, it does one write for CH1 followed by another write with CH2 bits added, Bits 7to4 are undetermined yet):
 CH1 - 0.0000 to  0.5000V ( Bit 3 = 0, Bit 2 = 1 )
 CH1 - 0.5001 to  5.0000V ( Bit 3 = 0, Bit 2 = 0)
 CH1 - 5.0001 to 20.0000V ( Bit 3 = 1, Bit 2 = 0 )
 CH2 - 0.0000 to  0.5000V ( Bit 1 = 0, Bit 0 = 1 )
 CH2 - 0.5001 to  5.0000V ( Bit 1 = 0, Bit 0 = 0 )
 CH2 - 5.0001 to 20.0000V (Bit 1 = 1, Bit 0 = 0 )

Long list of panel value and actual digital representations over the SPI, there is clearly either a formula or some kind of calculations done, one can see some arithmetic rounding issues, the values are identical for the both channels for the same amplitude value, the new fw will benefit of some calibration tables.

0.0000V - 0000
0.0003V - 0001
0.0004V - 0002
0.0005V - 0003
0.0007V - 0004
0.0008V - 0005
0.0009V - 0006
0.0010V - 0007
0.0020V - 000E
0.0030V - 0031
0.1000V - 02E1
0.2000V - 05C2
0.3000V - 08A3
0.4000V - 0B84
0.5000V - 0E65
=== KLAK ===
0.5001V - 0170
0.5007V - 0171
0.5031V - 0172
0.5043V - 0173
0.5055V - 0174
0.5068V - 0175
...
0.5100V - 0177
0.5200V - 017E
0.5500V - 0195
0.6000V - 01B9
0.7000V - 0203
0.8000V - 024D
0.9000V - 0297
1.0000V - 02E1
1.1000V - 03A2
2.0000V - 05C2
3.0000V - 08A3
4.0000V - 0B84
5.0000V - 0E65
=== KLAK ===
5.0001V - 0399
5.0037V - 039A
5.0098V - 039B
5.0147V - 039C
5.0208V - 039D
...
5.0500V - 03A2
5.1000V - 03AB
5.2000V - 03BE
5.5000V - 03F5
6.0000V - 0451
6.5000V - 04AD
7.0000V - 0509
7.5000V - 0565
8.0000V - 05C2
8.5000V - 061E
9.0000V - 067A
9.5000V - 06D6
9.9963V - 0731
10.000V - 0732
10.0025V - 0733
10.500V - 078E
11.000V - 07EB
11.500V - 0847
12.000V - 08A3
...
19.000V - 0DAD
19.500V - 0E09
19.9971V - 0E64
20.0000V - 0E65
=== BEEEP ===

For short time taking requests for special voltage values and thankfully accepts nice plots and graphs.

WANTED: DIGITAL SECRETARY TO MAKE A NICE SUMMARY DOCUMENT, EXPORTABLE TO PDF

Tomorrow, offset and phase, time permitting.

 DC1MC


10.500V - 0
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 21, 2018, 12:19:18 am
There are 17 switches and an optical encoder on the FP.  Would someone with a functioning (V 3.2+) unit document the state machine?  Most of the switches just select which input parameter is controlled by the optical encoder and the LCD panel switches.  It would also be helpful to know more about the RS-232 port and the LCD display.  That will let me start designing new FW.

I don't think it is worth spending much time on the FT FW aside from pure entertainment of trying the Fraunhofer attack.

I got my test monitor mounted to the wall, so I should be able to cable most of the bench tomorrow.  Then I'll install programming  pins and make an LA probing cable.  I've got an STM32F429 Discovery board, so I'll probably use that for the initial FW dev work as it has lots more resources and I know I can reprogram it.

I'm not clear on the "registers" DC1MC mentions.  Are these in the FPGA or the STM32?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 21, 2018, 12:34:26 am
There are 17 switches and an optical encoder on the FP.  Would someone with a functioning (V 3.2+) unit document the state machine?  Most of the switches just select which input parameter is controlled by the optical encoder and the LCD panel switches.  It would also be helpful to know more about the RS-232 port and the LCD display.  That will let me start designing new FW.

I don't think it is worth spending much time on the FT FW aside from pure entertainment of trying the Fraunhofer attack.

I got my test monitor mounted to the wall, so I should be able to cable most of the bench tomorrow.  Then I'll install programming  pins and make an LA probing cable.  I've got an STM32F429 Discovery board, so I'll probably use that for the initial FW dev work as it has lots more resources and I know I can reprogram it.

I'm not clear on the "registers" DC1MC mentions.  Are these in the FPGA or the STM32?

Cool, more hand and eyes needed.
Usually this the name for things implemented in the FPGA that are addressable, they are called registers.
We have an SPI interface and a number of these 32bit  registers in the FPGA, each with their own address (so far less than 8bits address space).
The registers that I've documented are in the FPGA and loaded/read via the SPI interface with 3 x 16bit word SPI transfers, first is the address (A), then the most significant bits in big-endian format(M) and the least significant bits (L) in the last transfer.
To start the new FW programming on the old FP we need the schematic, one member promised to work on it, but I didn't hear form him recently, if you want to use your own board then you need just an SPI interface to the signal board and 2 I/O pins for secondary functions, for start they can be skipped and  just use a 4 wire SPI.

Out of the registers block I have fully documented: 0x01,0x02,0x03,0x04,0x2D,0x2E and some bits in 0x06.
As functions we have now full control of the frequency and amplitude on sinus wave.
I've also posted a full configuration packet, that sets 20 registers at a time, for sine wave settings.
Tomorrow I will try to document phase and offset registers as well for the sine wave and channel enable bits (I have a hunch that they are also in register 6).

 Any questions welcome.

 Cheers,
 DC1MC

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 21, 2018, 01:11:29 am
Here is a plot of the "register" value vs voltage that DC1MC posted with the values converted from base 16 to base 10.

We really need for someone with a V3.2+ unit to verify that the voltage-register relationship is not borked.  I'll split off ranges and plot to check for calibration effects.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: SMB784 on January 21, 2018, 01:21:22 am
If my unit that arrives sometime next week is v3.2+, I will attempt to verify that. What is the necessary procedure for doing that?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 21, 2018, 01:31:46 am
Here is a plot of the deviation from a linear fit of voltage and register value based on my recollection that the DAC is 12 bit for the range from 5-20 V.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 21, 2018, 01:39:10 am
[
I've also posted a full configuration packet, that sets 20 registers at a time, for sine wave settings.


Where?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 21, 2018, 08:23:07 am
Reply #532 has a complete control message, the things there now are starting to make more sense, and if we have the phase and amplitude registers today, it will be even more clear.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 21, 2018, 12:47:41 pm
Hello everybody, some more registers have meaning now:

Phase shift:

 CH1 - Reg. 0x08
 CH2 - Reg. 0x09

Phase shift range:
 0x00002..0xFFFFF

Phase shift interesting values (sine waveform):
 000.000" - 0xFFFFF
 089.999" - 0xC0002
 090.000" - 0xBFFFF
 090.001" - 0xBFFFC
 179.999" - 0x80002
 180.000" - 0x7FFFF
 180.001" - 0x7FFFC
 399.999" - 0x00002

Offset:

 CH1 - Reg. 0x2B
 CH2 - Reg. 0x2C

Offset range:
 0x155..0xEA8 corresponding to -10.000V..+10.000V

NOTE: The relays activates according with the ranges described in the message dealing with Amplitude

Offset interesting values (sine wave 1.0000V amplitude)

 0.0000V - 0x07FF
-0.002V - 0x07FE
+0.003V - 0x0800

  As usual, taking requests for special values of interest, if any.

 Cheers,
 DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: ArthurDent on January 21, 2018, 01:42:32 pm
Is the phase shift table above correct or am I misunderstanding what it is indicating? Is the symbol " meant to be ° for degrees and if so is the last entry meant to be 359.999° ?
-Arthur

Phase shift interesting values (sine waveform):
 000.000" - 0xFFFFF
 089.999" - 0xC0002
 090.000" - 0xBFFFF
 090.001" - 0xBFFFC
 179.999" - 0x80002
 180.000" - 0x7FFFF
 180.001" - 0x7FFFC
 399.999" - 0x00002
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 21, 2018, 02:07:43 pm
Is the phase shift table above correct or am I misunderstanding what it is indicating? Is the symbol " meant to be ° for degrees and if so is the last entry meant to be 359.999° ?
-Arthur

Phase shift interesting values (sine waveform):
 000.000" - 0xFFFFF
 089.999" - 0xC0002
 090.000" - 0xBFFFF
 090.001" - 0xBFFFC
 179.999" - 0x80002
 180.000" - 0x7FFFF
 180.001" - 0x7FFFC
 399.999" - 0x00002

On the left are the values of phase as indicated on the Front Panel, the " was used instead of whatever sign indicating degrees was used on the FP.
On the right are the digital numbers loaded in the corresponding state machine register in the Signal Board FPGA via the SPI interface, I try to be very careful and repeat the measurements a number of times before I post something, but of course, nobody's perfect, so if you spot any possible issue, I can redo the measurement.

 Cheers,
 DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 21, 2018, 04:35:28 pm
A few stray thoughts:

The memory corruption may be a HW design fault.  In particular, failure to hold the power good pin off long enough for the PSU to stabilize. Mine worked fine until I turned it on for the Nth time.  My understanding is that same scenario applies to the other failures.  so potentially another thing that needs to be fixed.

The units may need individual calibration to correct for DAC errors.  The extent of the memory corruption makes any existing calibration tables highly suspect.  Recalibrating with limited equipment is likely to be quite challenging.

I looked at a couple of YoutTube reviews , one with a teardown,  of the JDS6600 which uses a different FPGA and generates the output voltages from a 5 V input.  It also uses the STM32F103, but the UI board is different. Unfortunately, neither of the reviews checked the voltage on the BNC ground.



Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 21, 2018, 04:44:48 pm
A few stray thoughts:

The memory corruption may be a HW design fault.  In particular, failure to hold the power good pin off long enough for the PSU to stabilize. Mine worked fine until I turned it on for the Nth time.  My understanding is that same scenario applies to the other failures.  so potentially another thing that needs to be fixed.

The units may need individual calibration to correct for DAC errors.  The extent of the memory corruption makes any existing calibration tables highly suspect.  Recalibrating with limited equipment is likely to be quite challenging.

I looked at a couple of YoutTube reviews , one with a teardown,  of the JDS6600 which uses a different FPGA and generates the output voltages from a 5 V input.  It also uses the STM32F103, but the UI board is different. Unfortunately, neither of the reviews checked the voltage on the BNC ground.

We need another unit to check, but it could be that there are NO calibration tables in the exiting fw, at lest for frequency, amplitude, phase and offset, that I've tested here. It could be that they measured once and determined the values and then left these trimmer resistors for tunning and that's it. The units will benefit for some individual calibration.
For the PSU they do offer a power-good pin that goes 0 when the power is there (it's a transistor with a resistor to base, of course, this one it's also not calibrated).

I hope that in the end I will produce enough data for the people that can't return their devices anymore and got more or less bricked, to be able to connect a blue pill board or something similar with an SPI interface to the SB and serial or USB to the outside and manage to control their board.
And for the people with better expectation to be able to aclibrate and control better their unit.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 21, 2018, 06:06:13 pm

We need another unit to check, but it could be that there are NO calibration tables in the exiting fw, at lest for frequency, amplitude, phase and offset, that I've tested here. It could be that they measured once and determined the values and then left these trimmer resistors for tunning and that's it. The units will benefit for some individual calibration.
For the PSU they do offer a power-good pin that goes 0 when the power is there (it's a transistor with a resistor to base, of course, this one it's also not calibrated).


The non-linearity of the amplitude-value pairs suggest that they put a lookup table in the STM32 which is populated during production test.  But that may be a "feature" that they don't actually use.

Can you measure the delay for the power-good pin?  I'm going to do that on mine as soon as I get the workbench rewired.  At the moment I have gear on new shelves, but no power yet.  I'm still severely outlet challenged. I need another 8-10 outlets, but haven't yet figured out where to put them.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Chris56000 on January 21, 2018, 06:13:43 pm
Hi!

I've got Mr. Tiong's books (both!) on PCB Reverse Engineering and I've started work on the schematic for the front–panel – I'm just laying–out the library symbols now before I draw out the schematic proper!

I'll draw up the Register Table once I've got a suitable copy of Office installed on my home lappy!

Chris Williams
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: ArthurDent on January 21, 2018, 09:32:12 pm
DC1MC -"I try to be very careful and repeat the measurements a number of times before I post something, but of course, nobody's perfect, so if you spot any possible issue, I can redo the measurement."

Perhaps I wasn't clear enough in my previous post. I had two points of confusion, the " vs  ° I could see, but where the last left entry in the table was 399.999, which is over 360°, I was wondering if I was missing something. The last value you got on the right looks logical for 359.999°. None of the results are not being questioned, just that there was a wrong digit entered.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 22, 2018, 11:43:25 am
DC1MC -"I try to be very careful and repeat the measurements a number of times before I post something, but of course, nobody's perfect, so if you spot any possible issue, I can redo the measurement."

Perhaps I wasn't clear enough in my previous post. I had two points of confusion, the " vs  ° I could see, but where the last left entry in the table was 399.999, which is over 360°, I was wondering if I was missing something. The last value you got on the right looks logical for 359.999°. None of the results are not being questioned, just that there was a wrong digit entered.
True Arthur, this was a brainfart while transcribing :(, of course is 359.999
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on January 22, 2018, 03:10:35 pm
I had a look at the JDS6600 teardown too ,despite looking very similar outwardly to the FY6600 ,its a very much simpler unit inside in all respects .Sorry Im not much use at programming ,so very little I can contribute to the great work you guys are doing in that respect.
I will be replacing the psu on mine once it arrives , I'll solder in the new output Ic's too .
That theory about the psu management pin sounds promising ,and surely wont be a major problem to fix if it turns out to be the weak link .
I did notice on the spec sheet that the distortion on the outputs reaches something in the order of 0.8% @ 0dbm, I wonder if this is something inherent in the DDS methodology or can be improved with a better powersupply and upgraded op-amps.
A proper Rf sheilding cage around the switchmode might also help in this respect as well as extra LC filters before the rails hit the main pcb, I found a lot of small switch psu's have extra space for these components ,but all too often these spaces remain unpopulated ,to save a few pennies. Theres always something gratifying about turning a sows ear into a silk purse .
The abillity to open up the firmware and turn a 15mhz unit into a 60mhz would truly be the icing on the cake ,and might serve as a wake-up call to the 'Feelers' guys to start treating their customers right.

DC1MC , RHB, Arth and Chris56 , sincerest thanks for your for your efforts and hard work .


Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 22, 2018, 08:12:39 pm
Hi Chris, welcome back after the hiatus, I'v thought that we've lost you   :'(, but now I hope you  :box: again. Soundtec, there is no programming so far, just some (bus) sniffing around, now and then please check this thread, who knows what nice things will pop.
My minimum goal is to bring the command decoding to the level where the signal board can be controlled with whatever thing has a SPI interface and 2-3 extra I/O, that means almost every fruit board and Arduino in the world.
Afterward I'll see if there is interest for more,  and of course participation from some other members.

I was trying to decode the channel on and off commands and along with the waveform change, they are way too much for Intronix, I can painfully log segments, but now it's clear that I need a better LA, with larger on device sample buffers and RLL compression.
I do kick myself that I didn't learn proper digital design, I was looking at all these affordable FPGA based ones, most of them have no sample compression (ACUTE up 600EUR, Digilent, others...) because they have a bit of memory on device and the rest have other strange design flaws, like this miserable and expensive junk that "uses PC memory" :(.
And I do have do ideas a proper USB 3 + FPGA LA design in a logic and pipelined way, but no way to implement them  :'( :'( :'(, even if I force mayself to start from almost scratch, getting the software infrastructure up and running and properly learning the design tools and simulators is way too much.
 
I repeat my appeal for an performant LA lease (2-3days, practically a week-end), if not, my meager finances will only let me try a SCANA Plus from IKALOGIC  for 95-100EUR or DS Studio clone, also any recommendation will be nice.


In the mean time let me tell you why I'm whining here, optimistic with the relatively easy capture for the sine waveform I've tried to change the waveform to square and also determine the on/off sequence for enabling the channels. Sadly this always triggers a full readout and refreshing of the LCD, and this is too much for the little Intronix and my attention span,  I can only get something like 8-10 registers even with compression, and it's easy to lose count when the control message has both readings and writings and around 60-100 registers moved around :(.

So right now I'm desperately sending price offers in fleabay, because if I order from China it will take ages. And trust me, it hurts to have to buy this crap and I have a good chance to be also useless.
 >:D note: If I'll ever make a commercial device with SPI interface, I'll make the clock high enough and space the transfers far enough to kill all the miserable LA, only elite LA owners should be able to decode it, at least here FeelTech did something good  ::) 

   Cheers,
   DC1MC
 



 

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: 2N3055 on January 22, 2018, 11:10:47 pm
I believe I did mention this before  Zeroplus LAP-C has compression and also something they call "filtering", which is basically "sample enable gating".. You can enable one of the inputs to  behave as a sort of "enable", gating,  so analyser is not spending memory when not enabled. On SPI protocol you can set it to work on chip select for instance, and it will sample only when CS is active...
Sampling to 200Mhz..
I have 16128, 16ch 128k samples depth. Useful little thing..
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on January 23, 2018, 01:18:06 am
On the subject of getting stuff delivered from China ,
I ordered quite a few items in early December ,some arrived within the specified time frame ,other stuff Im still waiting on .
Ive contacted a few of the sellers just to let them know Im still waiting .
Most just said hang tough another while ,but one offered to courier air freight another unit for something like 3 dollars US and work out what to do later if the original order arrives ,So really Im just saying if you see something at a good price from PROC it could be worth asking about what other delivery services are available , Im guessing the 3 dollars covers their costs,but you do see many places offereing courier delivery for way more more money ,like 20 dollars. Something small like a logic analyser might be cheap to fast track .

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 23, 2018, 11:55:02 am
I believe I did mention this before  Zeroplus LAP-C has compression and also something they call "filtering", which is basically "sample enable gating".. You can enable one of the inputs to  behave as a sort of "enable", gating,  so analyser is not spending memory when not enabled. On SPI protocol you can set it to work on chip select for instance, and it will sample only when CS is active...
Sampling to 200Mhz..
I have 16128, 16ch 128k samples depth. Useful little thing..

Well, good for you and the useful little thing, the problem is the "upgradeable" 16032 units from 2011-2013 are long gone, fleabay has exactly ONE 16034 unit for 225 EUR and looking at the German/EU specialty shops shows the thing in between 480 and 800EUR, and I will never pay so much.

What will be nice to have is a board with a robust Xilinx FPGA  + DDR2 RAM like this Papillio or the Pipistrello board, unfortunately ALL of them had brainfarts during design, instead of putting some Cypress FX, interfaces they've put either some lame USB to serial converters or even lamer PICs, making them completely useless for anything, and so these boards have more or less disappeared.

Why is nobody connecting one of these FX3 chips to a FPGA+tons of RAM (64MBit at least) and so a nice logic analyzer design on it, with RLL, gating and data streaming, using the on device RAM for ample buffering.
On such a device I definitely spend  5-600EUR, not on some unknown ASIC based crap that is not even USB3.

 OH well, I have to ask in forums if such a board already exists, maybe I do need to start a bit of digital design.

 Cheers,
 DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on January 23, 2018, 09:59:07 pm
So I am on a different path. Mind you, not a very successful one, but I may as well see it through.

The Frauenhofer powerpoint is even more explicit then the paper. Where the paper states something along the lines of "testing some samples showed that the attack may not work on other series", the powerpoint simply states "we could not get this attack to work on other series"
And they do write they also had access to the STM32F103C8. I am also not able to get it to work, but that maybe me being stupid.

So, just for the heck of it, I ordered the same development board they were using (with a STM32F051R8T6)
If I can get the attack to work on that, I know I am doing it right. And if it then still not works on the STM32F103C8, I know we are screwed.

Should be here soon too.  For some unfathomable reason,  buying it local in Netherlands is cheaper then on eBay. Weird.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 23, 2018, 10:25:02 pm
Strange thing Cybermaus, in Merkelania, the blue pills with the exact same chip as in the FP are something like 4,99EUR, I've got two of them, to use for the Fraunhoffer experiment, I was thinking to make the pseudo SWI debug interface on one of them and use it on the other and fine tunning the timing, I think it will get a bit better and faster then what the researchers used.
Right now I'm getting hold back by the lack of a proper LA (hint for the gear heads, part for a week-end of your cool LA, I promise not to run with it ;) so in the mean time I have to see how to solve this.

 Cheers,
 DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: 2N3055 on January 23, 2018, 10:58:19 pm

Well, good for you and the useful little thing, the problem is the "upgradeable" 16032 units from 2011-2013 are long gone, fleabay has exactly ONE 16034 unit for 225 EUR and looking at the German/EU specialty shops shows the thing in between 480 and 800EUR, and I will never pay so much.
My 16128  was 270 € (no VAT) in eleshop...

What will be nice to have is a board with a robust Xilinx FPGA  + DDR2 RAM like this Papillio or the Pipistrello board, unfortunately ALL of them had brainfarts during design, instead of putting some Cypress FX, interfaces they've put either some lame USB to serial converters or even lamer PICs, making them completely useless for anything, and so these boards have more or less disappeared.

Why is nobody connecting one of these FX3 chips to a FPGA+tons of RAM (64MBit at least) and so a nice logic analyzer design on it, with RLL, gating and data streaming, using the on device RAM for ample buffering.
On such a device I definitely spend  5-600EUR, not on some unknown ASIC based crap that is not even USB3.

 OH well, I have to ask in forums if such a board already exists, maybe I do need to start a bit of digital design.

 Cheers,
 DC1MC

Also was said, tool with Xilinx® Spartan®-6 FPGA and 2Gbit of buffer RAM is Digital discovery...  That one was 186 € (no VAT)... No compression, but it has segmented capture..
Maybe Digilent could be persuaded to add compression ??

Regards,

Sinisa
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 23, 2018, 11:30:43 pm

Well, good for you and the useful little thing, the problem is the "upgradeable" 16032 units from 2011-2013 are long gone, fleabay has exactly ONE 16034 unit for 225 EUR and looking at the German/EU specialty shops shows the thing in between 480 and 800EUR, and I will never pay so much.
My 16128  was 270 € (no VAT) in eleshop...
Now out of stock :(

What will be nice to have is a board with a robust Xilinx FPGA  + DDR2 RAM like this Papillio or the Pipistrello board, unfortunately ALL of them had brainfarts during design, instead of putting some Cypress FX, interfaces they've put either some lame USB to serial converters or even lamer PICs, making them completely useless for anything, and so these boards have more or less disappeared.

Why is nobody connecting one of these FX3 chips to a FPGA+tons of RAM (64MBit at least) and so a nice logic analyzer design on it, with RLL, gating and data streaming, using the on device RAM for ample buffering.
On such a device I definitely spend  5-600EUR, not on some unknown ASIC based crap that is not even USB3.

 OH well, I have to ask in forums if such a board already exists, maybe I do need to start a bit of digital design.

 Cheers,
 DC1MC

Also was said, tool with Xilinx® Spartan®-6 FPGA and 2Gbit of buffer RAM is Digital discovery...  That one was 186 € (no VAT)... No compression, but it has segmented capture..
Maybe Digilent could be persuaded to add compression ??
This is a thing that I will not pick it for free, my rant about can be read for your enjoyment in the other forum where I was asking for board suggestions  :-DD

Regards,

Sinisa

 Cheers,
 DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 24, 2018, 12:32:16 am
The good news:  I've got reliable connections to the bus and am getting data.  The MSO2204EA will collect 10 Mpts at 100,200,500 Ms/S & 1 Gs/S.

The bad news: I have no clue what I'm doing.  I've never used the LA features before other than a brief attempt which made clear I needed more reliable connections to the bus.  So I have several things to learn.  The scope LA , the AWG and the SPI bus..  I know what the SPI bus  is and  its strengths and weaknesses, but I have no practical experience working with it.  I've also never used a  LA before.

FWIW I was reading the JDS thread today.  The maker is very active in the forum helping owners and explaining the history of the very similar units.  Apparently two engineers designed all the units.  The JDS is the most recent version.  I think a major issue for FeelTech is the lack of an engineer with English language skills.  I urge everyone to ask for technical assistance from FeelTech.  JDS is providing the bus command protocol.  It's in Chinese so google translate is required for most, but they will help with problems.

Please!!!! Start a thread in the repair section of EEVblog so people can find things like bus pin assignments, etc.  Trolling through this thread to find a snippet of information is a huge waste of time.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on January 24, 2018, 06:23:04 am
I can arrange Chinese translations if needed. I am owed a few favours  :)

Now what and where do I probe or more to the point what is most useful? Thinking of populating the third header on the display board with pins to make it a bit easier?

Both my boards are V1.5 running v3.1 firmware btw

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 24, 2018, 07:29:25 am
The good news:  I've got reliable connections to the bus and am getting data.  The MSO2204EA will collect 10 Mpts at 100,200,500 Ms/S & 1 Gs/S.

The bad news: I have no clue what I'm doing.  I've never used the LA features before other than a brief attempt which made clear I needed more reliable connections to the bus.  So I have several things to learn.  The scope LA , the AWG and the SPI bus..  I know what the SPI bus  is and  its strengths and weaknesses, but I have no practical experience working with it.  I've also never used a  LA before.

FWIW I was reading the JDS thread today.  The maker is very active in the forum helping owners and explaining the history of the very similar units.  Apparently two engineers designed all the units.  The JDS is the most recent version.  I think a major issue for FeelTech is the lack of an engineer with English language skills.  I urge everyone to ask for technical assistance from FeelTech.  JDS is providing the bus command protocol.  It's in Chinese so google translate is required for most, but they will help with problems.

Please!!!! Start a thread in the repair section of EEVblog so people can find things like bus pin assignments, etc.  Trolling through this thread to find a snippet of information is a huge waste of time.

OK, the's take them in importance order last is bigger:
1) FeelTech and technical assistance: Only in China you can became an electronics engineer without proficient English, all over the world you're screwed if you try, I wish they would have exported just the textile industry there :(.
Asking for technical assistance: I have asked FeelTech really politely for very minor things, I've got exactly ZERO answers, if nobody knows English there it's understandable, if somebody ask for me of something in Swahily I won't be able to answer them, or just confirm that I've received an inquiry, that make sense. Ah, who am I kidding, they are the typical Asian company, eager to copy and profit from everything and considering a weakness and stupidity to share anything back, at least with non-Asians. I would so much LOVE to be proven wrong, but in 15 years or so while dealing with them I never had a cool story, and I haven't heard too many as well.  So JDS has a full specification of the control protocol from the FP to the Signal Board, all the registers and settings being explained, and compatible with FY6600 huh ? Willing to share it, but in Chinese ?
I would say bring it on, I've never seen a real unicorn yet :), and being a Mandarin Unicorn will not make it less beautiful ;).
Also a link to the JDS thread will help.

2) About actually doing stuff, I don't know if your scope has an individual LA or just has a protocol decoder using the analogue scope inputs.
<Beginner explain mode>
The commands are send via SPI protocol, the protocol uses 3 to 4 wires and it's a synchronous protocol, that means the data it's send and received being aligned with a common clock shared both by the sender and the receiver.
So you have to grab that clock before everything else, in our situation it's on pin 6 of the connector, the SPI protocol it's also a raycist  ;D  protocol, where there is a master and a number of slaves, they are selected with an individual selection pin, in our case there seem to be two slaves, but for basic stuff we can ignore it for the moment. Only master talks and generates the clock, and talks to the slaves using the MOSI signal (Master Out, Slave In), pin 8 and listen to what are they saying using the MISO pin (Master In, Slave Out), pin 7.
There is also a Slave Select or Chip Select pin, that goes to 0 usually, to wake up the slaves and tell them that the master is gonna talk and they better be listening and answering or else... (very raycist ;)
This is our pin 5, usually if you have a LA you use this pin on falling edge to trigger acquisition, if you have a two channel scope with separate sync input you put it there and use it as trigger, if you have a 4CH scope you can still put it on the sync input but also on one of the channels, and if you have just a 2 channel scope without separate sync, you ignore it and use the clock signal to trigger, but it's a bit on the edge.

So, with a two inputs scope you can see one direction only M->S or S->M, with a 4 inputs scope you can see and decode fully the SPI interface, same with a proper LA.

Now the clock and transfer size varies, in our case the clock it's 18MHz and the transfer size or word size it's 16 bits, an LA should be  used in sampling mode, with a sampling frequency of at least 100MHz to get reliable results. Scope ca. 50ns/div, depends on what they recommend for SPI protocol decoding in regard with the clock frequency.

On the Signal Board side, in the FPGA, there are a number of individual addressable entities called registers, a register is written or read using 3 x 16bit transfers, one for address and two for the data to be written or read, you can see a bit behind some of those registers read and explained, my LA has reached it's limits, so I'm waiting to get a proper one.

If your protocol decoder works, you should be able to get the registers values while doing different settings (compare first with the ones already discovered to make sure that everything it's set OK ).
In the evening I will make a new post in the Repairs forum, summarizing the details spread around here and I can assist anyone trying to get the information or trying to translate this mystical JDS document :).

I have to run for work now, cheers.

</Beginner explain mode>
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on January 24, 2018, 07:35:12 am
Despite all the warnings and firmware issues I decided to buy the unit beginning this month and it still somewhere between China and me. But I expect the unit to be delivered next week if customs is playing nice this time.

I was planning to help with the protocol decoding but all the high speeds and long packet pauses got me of this helping plan since I don't have a capable LA. only a 4ch 200Ms scope with limited memory.

Making a schematic of the boards should be no big deal as from the pictures most of it is clear enough already. The front panel is still a bit unknown to me as there are no high res pictures available yet.

I plan on making a linear PSU with 6 outputs 2x +5, +-13.8V and +-5V for the 5 legged op amps to replace the 7805 and 7905.

Hope to make a new front panel controller/software with a combined effort of us all, only for a different font would be top notch :D

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on January 24, 2018, 08:11:56 am
Scope is a 4channel 100MHz with uart spi i2c can bus decoding etc.

Just for my information as much as anyone elses I have buzzed out the header on the front panel because as has been mentioned this thread is getting a little bulky to follow and got the following.

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 24, 2018, 11:56:33 am
Scope is a 4channel 100MHz with uart spi i2c can bus decoding etc.

Just for my information as much as anyone elses I have buzzed out the header on the front panel because as has been mentioned this thread is getting a little bulky to follow and got the following.

Well, now you know where to hook you scope  ;D, waiting for the first results, if possible try to reproduce the Sine wave result that I have posted, there are 20 registers set ( 30 SPI transfers) and then try for example disabling and re-enabling of a channel, this updated the LDC and transfers muuuuch more data, this killed my little Intronix.

Nice picture with comments, we should include it in the official documentation in the new thread, I'll do a fully disassemble of my FP to get pictures and try to map the buttons and the LCD connector.
Maybe you can post it completely along with others to help DerKammi with the schematic capture.

@DerKammi Let's not be swept away by all the negativity, for the price it's really a good development platform for people that want to study and understand many things, from MCU to FPGA programming, direct digital synthesis of signals, analog stuff and much more (even power supply design and pitfalls). And when it works it makes a usable device and if fully moded and fitted with our new fw ;) will make a killer device.

 Cheers from the lunch break, DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on January 24, 2018, 12:08:47 pm
@DerKammi Let's not be swept away by all the negativity, for the price it's really a good development platform for people that want to study and understand many things, from MCU to FPGA programming, direct digital synthesis of signals, analog stuff and much more (even power supply design and pitfalls). And when it works it makes a usable device and if fully moded and fitted with our new fw ;) will make a killer device.

Oh I'm not at all. The reason of the purchase is the modding capabilities of this device. Also a new firmware is something which I find to have a real goal of writing software for. Taking also those small embedded projects to the next level in my hobby environment.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 24, 2018, 04:32:49 pm
Ask for a pinout and get a lecture on PC :-(

The FD JDS6600 thread is here:

https://www.eevblog.com/forum/testgear/anybody-know-anything-about-this-signal-generator/msg1233239/#msg1233239 (https://www.eevblog.com/forum/testgear/anybody-know-anything-about-this-signal-generator/msg1233239/#msg1233239)

Sadly, I am now completely borked.  I was getting SPI traffic last night but didn't know which pins to assign in the LA.  This morning when I powered it on, the LA reported "buffer overflow".   After that there was no detectable bus traffic.

After I dug through all the excess verbiage and found the pin assignments I discovered that except for an occasional burst of noise on all channels of the SPI bus, there is NO traffic.  The beeper makes noise, but maybe one out of 10-20 beeps is accompanied by bus traffic.  Just in case it was an error setting up the LA, I switched to using the analog channels.  It's just noise.

Two pins are logic high and two are logic low when it is idle.  There is now no output from either channel.  There was earlier this morning, but I could not change the waveforms.  Power cycling seems to be fatal.

Nothing left now for me to do except to treat the FP as a crappy dev board with some buttons and an unknown LCD unless someone comes up with a FW image or the bus protocol.  It will be interesting to see what eBay and Paypal have to say.  I just wish it were easier to contact them.

I'll probably order an FD JDS6600 in the next few days to have a decent AWG.  But I'm going to read the full thread first.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 24, 2018, 05:53:35 pm
@rhb: Oh man, this is really terrible  :palm:, it seem that there really is something that kills them, the firmware or the power supply must be really bad, because I've abused a blue pill board with the same chip and practically 0 power filtering, besides an anemic cap, and I still wasn't able to bork it.
Kindly please tell us the firmware version, how is the defect manifesting (besides no signal) like is the display still  correctly showing up info, the channel LEDs are going on and off when you enable and disable the channel, and finally, is the unit recognized and controllable from the PC, can you try there to set up a sine waveform from the PC ?
The I/O pins of the STM are pretty resilient to grounding and short-circuiting and on the configuration connector there is no power, just ground.
For the sine wave we have the SPI control sequence, to set up almost everything, we're missing the initialization sequence and then you can connect anything that can do SPI with 16bit word ( again a blue pill will be the best and very cheap).

I'M MAKING AN APPEAL TO GERMAN READERS THAT ARE PLACED IN THE MANNHEIM-HEIDELBERG-KARLSRUHE-STUTTGART AREA AND HAVE A PERFORMANT LOGIC ANALYZER FOR LEASING IT TO ME FOR A WEEK-END OR I CAN COME WITH MY UNIT TO THEIR PLACE AND MEASURE THE BUS TO GET THE PROTOCOL OUT OF THE WAY !!!


It's a four hour work with two persons, and I can also provide the beer and Würstchen, or a snack/beverage of choice plus he'll get all the forum glory and karma  :-+ .

If by this week-end I'll not find a better analyzer, I'll try to proceed with my Intronix to get at least the initialization sequence out of many restarts, if it holds it holds, if it dies it dies, if not at least we can still use the borked units until the fw is recovered/rebuild.

Keep fighting,
DC1MC

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Diabolo on January 24, 2018, 06:05:34 pm
Hello,

It would not be electrostatic discharge that would be a problem ?

Diabolo
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 24, 2018, 06:12:56 pm
Hello,

It would not be electrostatic discharge that would be a problem ?

Diabolo

That could be a cause, but I believe everybody here knows the basic rules for ESD protection and rsd isn't a novice. Also the defect appeared at power-on not when wires were moved around, AFAIK it was working OK and rhb turned it off for the evening and when turned back it was not working anymore. There are so many reports of these just dying at power-up that it seems there is a catastrophic design fault, wonder if it's sw or hw  :o.

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Diabolo on January 24, 2018, 06:24:51 pm
Hello,

It may be a "weak" component that dropped at startup.
I have a FY2300H (color blue) version 3.2 (bought July 2017) and I have no problem, its power is 5V - 1A by a PS style charger GSM.


Diabolo
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 24, 2018, 07:00:49 pm
I have started a thread in Repair "FeelTech FY-6600 Corrupt Flash Repair" which summarizes what information we have.  If you post there *please* be brief and clear.  Discussion should remain here.

FWIW I'm working on an ESD mat and the humidity is 100%.  With exactly identical screens on multiple units after corruption, ESD seems an unlikely cause.

I'm about to start testing the FP separated from the SB.  I have other projects and this is looking a lot like what we call a "dry hole" in the oil industry.  So further efforts by me will be sporadic.






Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on January 24, 2018, 07:46:51 pm
Hi there!

Nice thread and a lot of interesting things to read.
I've got a FY6600 60Mhz with firmware V3.2.
You will find attached a dump of the flash memory for the records. (@cybermaus: nice how to... )

I have also hooked up my LA to the board and will try to help gathering informations on the FP<-> FPGA protocol (just a matter of free time).
I will first try to see if there are obvious differences in the V3.2 protocol with what DC1M1C already described for V3.1.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 24, 2018, 08:40:29 pm
Welcome on board fremen67  ^-^, I hope that you'll be the next one to get some data out of this cable.
Now it's the battle royale of the Logic Analyzers, I've wanted to see how much it's the initialization sequence when one channel is activated and the whole LCD is refreshed, as my little LA doesn't stand a chance to log the sequence I started to count the SPI transfers at least.
BLOODY ROTATING HELL !!!
5608 transfers !!!
Whoever has a LA that is able to log this, please tell, I want one.
The novelty is, as opposed with setting frequency, amplitude and such, this time I have managed to capture the one SPI register read operation, the exact last one even :).
They differ from write operation, that have one SPI transfer 3x16bits words (address + 32 bit value), the register read operation first sent the address (one transfer MOSI) then, a bit later, reads 32 bits in two transfers form the slave (MISO).
Please have a look at the attached picture, the full read operation is between cursors A and B.

Good that I've found an excellent FPGA board with lots of DDR3 ram and USB 3.0 interface and I've reconnected with an old digital designer friend, this calls for a serious LA  ;D

 Cheers,
 DC1MC

 


 
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 24, 2018, 08:54:24 pm
I've separated the FP from the SB.  If I power up the FP without connection to the SB it just displays the FeelTech logo.  No other information.  So there is some communication from the SB to the FP.

I'm getting waveforms out again, so it appears that I caused problems when I soldered wires to the 8  bit bus connectors making the connections to the SB header unreliable.   In retrospect, I should have cut the cable in the middle and soldered the ends together to take the grabbers.

I observed some large globs of flux which I have cleaned off with isopropyl.  I've encountered problems in humid climates with absorption of moisture affecting signal integrity.

@DC1MC the picture is missing
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: texaspyro on January 24, 2018, 09:00:51 pm
Are you qualifying the logic analyzer clock with the SPI chip select signal for the signal board?  That will limit captures to just those for the signal board.  Most analyzers have a way to qualify the clock,  otherwise you may need to add an external gate.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on January 24, 2018, 09:40:43 pm
Here is a capture of the Power On initialization sequence for the main 6 signals : 4.5 sec,  29403 transfers... A lot of material to study ...

PA1 seems to be some sort of /FPGA Ready signal. It is true at the beginning then falls just after MISO has been released. It last for 180ms
PB 11may not be a second CS as already suggested but rather a /Register Select signal. It is always down when sending the register number to the FPGA then up when sending the value for it.

If you want to have a look at the power on sequence, you need to download Dsview 0.98 here: http://www.dreamsourcelab.com/download.html (http://www.dreamsourcelab.com/download.html)
Just open the .dsl file and the Decoder window. The screenshot shows you what you can see when zooming
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on January 24, 2018, 10:19:05 pm
... I've wanted to see how much it's the initialization sequence when one channel is activated and the whole LCD is refreshed, as my little LA doesn't stand a chance to log the sequence I started to count the SPI transfers at least.
BLOODY ROTATING HELL !!!
5608 transfers !!!
I attached 2 captures: the OFF to ON and then ON to OFF sequences for CH1: Sine, Freq.10Khz, Amp.5V, Off.0V, Duty.50%, Phase.0, same on CH2 which remained OFF.
EDIT: I just noticed that with V3.2 I have 6024 transfers in that case compared to your 5608 ...

Whoever has a LA that is able to log this, please tell, I want one.
The captures where made using a DSLogic Basic (55€ on aliexpress) upgraded to the Plus version by adding a 256Mbit RAM Buffer (2€ @mouser). But even the Basic version can stream the Power On initialization sequence with simple Triggers (6 channels@ 50Mhz or 3 signals @100Mhz).
Having the buffer allows you to setup complex triggers (like a specific register value) at higher sampling rates: @400Mhz for 4 signals (You can also activate RLE compression when needed).
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on January 24, 2018, 10:32:30 pm
I'm getting waveforms out again, so it appears that I caused problems when I soldered wires to the 8  bit bus connectors making the connections to the SB header unreliable.   In retrospect, I should have cut the cable in the middle and soldered the ends together to take the grabbers.
Cutting wires is a little bit extremist  :)
With this type of connector, you don't need grabbers. I would suggest to solder head to head 2 rows of 8 pins. You release the connector from the board, insert one side of the 8 pins in the upper part of the connector and then replug the connector. This will lock the pins in place. Than you connect on the other side of the 8 pins directly your LA wires (or eventually scope probes). Have a look at the photo I posted before, this should be clearer than my explanation  ;)

EDIT: Typo.. "lock" and not "look".. sorry
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on January 24, 2018, 11:41:04 pm
... I've wanted to see how much it's the initialization sequence when one channel is activated and the whole LCD is refreshed, as my little LA doesn't stand a chance to log the sequence I started to count the SPI transfers at least.
BLOODY ROTATING HELL !!!
5608 transfers !!!
I attached 2 captures: the OFF to ON and then ON to OFF sequences for CH1: Sine, Freq.10Khz, Amp.5V, Off.0V, Duty.50%, Phase.0, same on CH2 which remained OFF.
EDIT: I just noticed that with V3.2 I have 6024 transfers in that case compared to your 5608 ...

It is even worse than that.. I was only capturing the first train of tranfers. In fact when you switch ON CH1, there are 3 trains of transfers.. 12111 transfers in total. I could not find a difference when analysing the captures of CH1 OFF->ON and ON->OFF... just because the first train is identical... so 6024 transfers less to search in  ;)

EDIT: 12111 transfers for one command :scared:
Reg 0x05 = 0  -> CH1=ON, CH2=ON
Reg 0x05 = 4  -> CH1=OFF, CH2 = ON
Reg 0x05 = 24  -> CH1=OFF, CH2 = OFF
Reg 0x05 = 20  -> CH1=ON, CH2 = OFF

So if I make no mistakes:
Reg 0x05:bit5=0/1 -> CH1=ON/OFF
Reg 0x05:bit2=0/1 -> CH2=ON/OFF

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 25, 2018, 12:40:46 am

Cutting wires is a little bit extremist  :)
With this type of connector, you don't need grabbers. I would suggest to solder head to head 2 rows of 8 pins. You release the connector from the board, insert one side of the 8 pins in the upper part of the connector and then replug the connector. This will lock the pins in place. Than you connect on the other side of the 8 pins directly your LA wires (or eventually scope probes). Have a look at the photo I posted before, this should be clearer than my explanation  ;)

EDIT: Typo.. "lock" and not "look".. sorry

What is the connector and where can you buy them?  I looked for a long time online without finding anything.  I made a new connector using an 8 pin "Dupont" connector, but it doesn't make reliable connections.

My original intent had been to make a probing harness, but I got impatient.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on January 25, 2018, 01:38:40 am

Cutting wires is a little bit extremist  :)
With this type of connector, you don't need grabbers. I would suggest to solder head to head 2 rows of 8 pins. You release the connector from the board, insert one side of the 8 pins in the upper part of the connector and then replug the connector. This will lock the pins in place. Than you connect on the other side of the 8 pins directly your LA wires (or eventually scope probes). Have a look at the photo I posted before, this should be clearer than my explanation  ;)

EDIT: Typo.. "lock" and not "look".. sorry

What is the connector and where can you buy them?  I looked for a long time online without finding anything.  I made a new connector using an 8 pin "Dupont" connector, but it doesn't make reliable connections.

My original intent had been to make a probing harness, but I got impatient.

I guess what I wrote was not clear :) When I wrote "With this type of connector" I was talking about the type of the white connector used on the board. Because it is huge and has 2,54 mm spacing you can just use classical 2.54mm male breakable Header Strip. I am sure you have plenty of them in your drawers. You cut 2 rows of 8 pins, solder them together by the shorter side and that's it. It is the same idea as putting needles in the rear side of the connector to access the contacts. With this photo you will find it obvious  ;)
The tip is to remove the connector from the board before inserting the header pin "connector" in it: it is much easer to put it in and afterwards when you reconnect your connector on the board, the header pins can't move.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 25, 2018, 02:20:32 am
If that were a M-F pair I could see how you could put grabbers on between the plastic strips.  However, I'm not getting reliable connections using female connectors  on the male board  pins. The header pins on the board  are much shorter than the headers in your picture.  I cut back the plastic on the F connector, but the sockets don't stay in place when I try to press the connector in place.

You can plug the setup you show into the FP or SB, but they don't work without talking to each other.  So I'm still unclear how what you are suggesting would work unless you had a pair of F-F cables.

Which still leaves my question,  What is a source for those cable connectors?  Or  replacement  cables.

[edit]

I found the connectors.  It's the JST XH series.  Digikey carries them.  Unfortunately, the crimping tool is *very* expensive.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 25, 2018, 03:26:48 am
Here's a possible option for the LA problem;

https://www.youtube.com/watch?v=_LnZrXrdC00 (https://www.youtube.com/watch?v=_LnZrXrdC00)

An FPGA and some compression logic would be nice, but for $45 and 200 MB/S it looks as if it might well do the job for this problem.

I opened up the Instek LA pods and they have a bunch of ADCMP561s and a bunch of discretes in addition to some other stuff.  Pods are marked 100K ohms and 40 V.

So there's a bit more than just an FX3 to making a proper LA, but as we are dealing w/ 3.3 V logic it might be worth a gamble.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DaveR on January 25, 2018, 03:49:14 am
I found the connectors.  It's the JST XH series.  Digikey carries them.  Unfortunately, the crimping tool is *very* expensive.

You don't need a rip-off crimping tool for XH connectors - just use lengths of FTP network cable wire and solder them to the pins, then use a pair of needle nosed pliers to fold the "wings" of the pins over the insulation to grip the wires.  Just use minimal amounts of solder so that you can still insert the pins into the plastic shell.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: CustomEngineerer on January 25, 2018, 04:21:45 am
If that were a M-F pair I could see how you could put grabbers on between the plastic strips.  However, I'm not getting reliable connections using female connectors  on the male board  pins. The header pins on the board  are much shorter than the headers in your picture.  I cut back the plastic on the F connector, but the sockets don't stay in place when I try to press the connector in place.

You can plug the setup you show into the FP or SB, but they don't work without talking to each other.  So I'm still unclear how what you are suggesting would work unless you had a pair of F-F cables.

Which still leaves my question,  What is a source for those cable connectors?  Or  replacement  cables.

[edit]

I found the connectors.  It's the JST XH series.  Digikey carries them.  Unfortunately, the crimping tool is *very* expensive.

Pretty much any cheap generic jst/dupont crimpers will work. You can even use the cheap sockets for making the dupont connectors, but instead of putting the plastic housing on just put some shrink wrap. I made the one in the picture the other day with exactly what's in the picture (~$10 for the crimper 5 - 10 years ago, ~$1 for the sockets). As for fremen67's suggested way of connecting, you are way overthinking what he is saying. Go back and look at the first picture he posted where he is already hooked in. He is not using (or suggesting to use) grabbers. The multicolor cables are going back to the LA, no grabbers necessary, the LA cables just plug directly into the adapter. And the adapter is being pushed directly into the original connector that is already in the generator. He is just suggesting to pull the cable from the generator board before trying to push the adapter into the back of it to allow the adapter pins to go in easier, then the generator cable gets plugged directly back into the board.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on January 25, 2018, 04:37:41 am
Long pin header seems to work fine for me . Plenty of length for clips or probes.  :)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 25, 2018, 07:21:31 am
Holly cow, you go to sleep a bit depressed and you wake up with a lot of cool activity  ^-^ ^-^ ^-^

@fremen67  Vive la France !!! finally data, sweet data, to analyze  8) !!! Than you so much !!!
Now some comments:
Basic architecture:
- Having -PWRGOOD and -FPGARDY signals are a good and logic design decision, I did the same as @rhb and started the FP with the data connector out, it now explains why it blocks waiting for the two signals to drop, for the sake of experiment I will try to artificially pull them down and see how the FP display looks like, especially what waveform data is selected by default and how the picture of it looks.
- Having an address/data selector pin it's a bit meh, if the registers are always 32bits, it will introduce a minor complication while writing the new firmware, I'm curious how they switch in between reading and writing a register from the FPGA pov, because this will help us to produce the first and most important new firmware routines: register read and write.
- Detaching the actual configuration commands from the stuff that displays the waveform on the LCD, that IMO is the bulk of the transfers and should consist mostly of reads (sample the waveform description in FPGA to do a drawing ?!?!?),  because for the non-FP firmware, we don't need to bother with little miserable pictures for starters.

Current data sets:
@fremen67
- I want to kindly ask you to do an 100MHz sampling "reference" capture for the initialization sequence, the SPI clock it's 18MHz and Shannon may wink from where it is  >:D, so activate the RLE and buffering and get the full initialization seq for reference, I'll have to munch on it, it's a lot of research, for example I'm really curious if the FP reads the data from the SPI Flash first and then push it to the FPGA.
About the On/Off captures and the multiple train of pulses, this sounds a bit weird, I did my captures with CH1 already in the OFF state and counting the pulses for the push to ON, and even if my little LA it's outclassed by the diarrhea of data, it was counting reliably the number of transfers (NCSS going down), putting one transfer more in the trigger settings was not triggering it,
If you can repeat (again as 100MHz sampling) the measurement with the CH1 already in OFF state before starting measurement I will double grateful.

Logic Analyzer:
I've found this excellent Artix boards with lots of RAM and Cypress FX3 interface, and a digital designer to help me, the seller send the schematics and SDK and it actually looks sane, I'll try to produce an updated DSPro+ thingie to not be caught off-guard if the next project with an 33MHz SPI clock ;). The analog front end will be a pleasure to design  8). I'll let you know if you're interested, PM me, it's off-topic on this thread.

 See you all in the evening,
 DC1MC 

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on January 25, 2018, 12:32:56 pm
The captures where made using a DSLogic Basic (55€ on aliexpress) upgraded to the Plus version by adding a 256Mbit RAM Buffer (2€ @mouser). But even the Basic version can stream the Power On initialization sequence with simple Triggers (6 channels@ 50Mhz or 3 signals @100Mhz).
Having the buffer allows you to setup complex triggers (like a specific register value) at higher sampling rates: @400Mhz for 4 signals (You can also activate RLE compression when needed).

Which chip did you use? I like the idea of this kind. ^-^
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 25, 2018, 03:07:44 pm
I tried what fremen67 does, but with individual wires which proved unreliable.  Wish I had thought of using a header like that.  Very slick. 

The "dupont" style connectors I have (eBay assortment) have the sockets recessed too far to reach the board pins.

So I'll be filling in the hole i dug once I get some connectors and a crimping tool.

BTW I'm *very* interested in a more capable LA than what the Instek provides.   Something that just sends transitions to the PC for recording and which can be configured to sample at some multiple of the target clock.  So please start a thread in the Projects section.  I've been planning to get a miniZed because of the widespread use of the Zynq in scopes.  Getting another would not be an issue.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: gbraux on January 25, 2018, 07:11:17 pm
Hi. I am new to the forum, so a big hello from Paris, France.

I have just received my FY6600 (30Mhz) from Aliexpress and ... looks like they have updated the PSU :-)
I also ordered some IEC connectors at the same time ... but I won't bother making the ground hack : Ground-BNC to Ground-Earth = 300mV :-)

FW Version : 3.2
Main board Feeltech branded V1.501
PSU brand is "SUOR". Most immediate visual difference with the previous PSU is the banding (used to be FeelTech) , and they have removed the unpopulated headers we used to use for connecting ground-earth(IEC hack). There may (for sure) be some other differences, but not an expert ...

Guillaume.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on January 25, 2018, 09:53:26 pm
Hi Guillaume,
welcome to the forum .
That sounds like good news ,maybe the original supply was responsable for the dodgy batch ,
I said I might as well repost this image from a previous comment for the purposes of comparison.
not the greatest of images ,maybe theres a better one to be found .
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on January 25, 2018, 09:58:00 pm
Only difference I can spot for sure from those two photos is the Yellow mains input filter cap is gone .
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on January 25, 2018, 10:12:29 pm
Slightly better image here ,
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on January 26, 2018, 12:36:10 am
- Having an address/data selector pin it's a bit meh, if the registers are always 32bits, it will introduce a minor complication while writing the new firmware …
But it is more robust  as a falling edge of CS while having RS low always indicates the beginning of a register write command thus insuring synchronization…

- I want to kindly ask you to do an 100MHz sampling "reference" capture for the initialization sequence, the SPI clock it's 18MHz and Shannon may wink from where it is  >:D
In streaming mode the LA can sample up to 3 signals @100Mhz  and up to 6 @50Mhz (In buffer mode there is no way that it can capture 4.5 sec of signal, even with RLE activated…).
I recorded  yesterday 2 captures of the init sequence @100Mhz (MOSI-MISO-CLK) and @ 50Mhz (MOSI-MISO-CLK-/CS-/RS) and then checked that the SPI decoded values where exactly the same. So appart from cosmetical consideration on CLK not beeing a perfect square signal, all the SPI decoded value should be correct in the 50Mhz capture with the benefit of having CS and RS at the same time.
I will post a 100Mhz capture for you but I find the 50Mhz one much easier to read.

Regarding Shannon winking I think he could be reassured and RIP  :)
The Shannon Sampling Theorem states that your sampling rate should be at least twice the highest frequency contained in your signal, that is 18Mhz here from CLK, thus the sampling rate should be at least 36Mhz. There is a rule of thumb that says you need at least 4 times the highest  frequency to be on the safe side (that is 72Mhz here) but hey … with 50 Mhz we are somewhere in the middle… and it works.

About the On/Off captures and the multiple train of pulses, this sounds a bit weird, I did my captures with CH1 already in the OFF state and counting the pulses for the push to ON, and even if my little LA it's outclassed by the diarrhea of data, it was counting reliably the number of transfers (NCSS going down), putting one transfer more in the trigger settings was not triggering it,
If you can repeat (again as 100MHz sampling) the measurement with the CH1 already in OFF state before starting measurement I will double grateful.
This is exactly what I did yesterday (about 15 times I think, maybe more...and @100Mhz) plus the other way (ON to OFF). Don’t forget that :   
-   There is more than 172ms between train 1 and 2
-   The revision I have is V3.2 (I think you have 3.1 ?)
That could explain the different behaviour.

For the init sequence capture, I would recommend that you place a cursor just before the first SPI transaction (around 66.66 ms) and change the protocol decoding start from "Start" to "Cursor 1" (see photo)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on January 26, 2018, 12:47:04 am
The captures where made using a DSLogic Basic (55€ on aliexpress) upgraded to the Plus version by adding a 256Mbit RAM Buffer (2€ @mouser). But even the Basic version can stream the Power On initialization sequence with simple Triggers (6 channels@ 50Mhz or 3 signals @100Mhz).
Having the buffer allows you to setup complex triggers (like a specific register value) at higher sampling rates: @400Mhz for 4 signals (You can also activate RLE compression when needed).

Which chip did you use? I like the idea of this kind. ^-^

This one : https://www.mouser.fr/ProductDetail/913-4816M16A2TG6AGTR (https://www.mouser.fr/ProductDetail/913-4816M16A2TG6AGTR)
But you then have to either change the USB VID/PID in the program (DSview) or in the onboard eeprom so that it is seen as a "Plus" and not a "Basic" one.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 26, 2018, 01:47:28 am
For those who are interested I started this thread:

https://www.eevblog.com/forum/testgear/what-is-the-state-of-the-art-for-a-reasonable-diy-la/ (https://www.eevblog.com/forum/testgear/what-is-the-state-of-the-art-for-a-reasonable-diy-la/)

to focus on providing an affordable high performance LA solution  using COTS HW and FOSS software.

PS I'll order my repair parts manana.    Sometimes it's just more fun than I can stand.  Makes me want to go hang sheet rock.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DaveR on January 26, 2018, 01:59:08 am
I have just received my FY6600 (30Mhz) from Aliexpress and ... looks like they have updated the PSU :-)

Hi Guillaume - the power supply in yours is the same as in mine (also v3.2 firmware).  It's also the same as was used in the FY3200 series, when the board was labelled v1.1; ours are v1.6, but there's no visible difference between the two versions that I can see.  I'm hoping that the change of the main board from v1.50 to 1.501 might just be the correction of the flaw in the design, and not just a "suck it and see" attempt to sort it out.

Dave
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: ArthurDent on January 26, 2018, 02:44:58 am
The new power supply in the unit gbraux just received doesn’t instill confidence in me that FeelTech is trying to improve the FY6600. As soundtec mentioned the yellow cap on the input has been eliminated (and the resistor next to it) plus there are other changes. It appears from the photos of the 2 supplies that the ‘new’ board material is phenolic where the old one was fiberglass, which I consider better. The cut gap in the old FY6600 power supply board under the optoisolator that is a safety feature has been eliminated as has the grounding pads already mentioned. All the parts on the secondary side seem to be the same values as near as I can see except the larger of the 3 diodes near the transformer (that I assume is for the +5 supply) is physically smaller on the new board.

I get the feeling that the new supply isn’t better at all and they just cost reduced it to save a few more cents and it certainly won’t improve the performance at all and it could be worse.  Using the same supply that is used in the FY3200 series certainly would be a cost cutting move. I wonder if there are other similar changes to the main board, it would be interesting to see side by side photos to see. My guess the main board has remained the same.

So far my FY6600 is still working but I have my fingers crossed.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on January 26, 2018, 07:11:33 am
Hi. I am new to the forum, so a big hello from Paris, France.

I have just received my FY6600 (30Mhz) from Aliexpress and ... looks like they have updated the PSU :-)
I also ordered some IEC connectors at the same time ... but I won't bother making the ground hack : Ground-BNC to Ground-Earth = 300mV :-)

Did you measure AC or DC?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on January 26, 2018, 08:49:32 am
This one : https://www.mouser.fr/ProductDetail/913-4816M16A2TG6AGTR (https://www.mouser.fr/ProductDetail/913-4816M16A2TG6AGTR)
But you then have to either change the USB VID/PID in the program (DSview) or in the onboard eeprom so that it is seen as a "Plus" and not a "Basic" one.

Whoaa €20 shipping, that is steep. Got 1 spare by coincidence? It would make a nice way of tackling the Feeltech hobby board :)

Where did you change these in the DSview? in the source code?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on January 26, 2018, 09:07:29 am
Are you sure? I get a "this product ships free" message for mouser. Did you check mouser.nl or mouser.fr?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 26, 2018, 09:08:33 am
@everybody - sorry some family thing to do got hold of my time, now I'm done, so back to our business.

@DerKammi - Fleabay to the rescue, Mouser, Digikey and friends have very fast and reliable shipping, but also very expensive. It's worth getting lots of stuff to offset the transport costs. They really are "en-gorre" sellers mostly.

@fremen67 - Thanks for the extra captures, I was wondering how is the FPGA detecting between reada and writes, I see on my captures that there are two CS cycles, one with the address CD goes up and then goes down again for data. Anyway, I'll have a full week-en, the DS Studio compiled nicely on my Ubuntu 16.04.

@rhb - I'll add to the LA topic you've created, I'll post soon the github to the code of the seller along with schematics of the board I've chose, call for features and some ideas for high-speed, high-impedance, pods, both active and passive. I think there are enough "cheap affordable" analyzers that on anything over 33MHz are useless, time to try a mid-range design with COTS stuff.

@Guillaume To me the new PS doesn't look way better, and frankly, the voltage gradient against ground of 300mV looks waaay too good even for hi-end unearthed SMPS. 


 Cheers,
 DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on January 26, 2018, 09:32:38 am
Are you sure? I get a "this product ships free" message for mouser. Did you check mouser.nl or mouser.fr?

I'm afraid the warehouse is in France, under 50 I get 20 shipping.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on January 26, 2018, 09:50:43 am
Oh yeah. When I actually press "order" they add the usual 20. Sorry.
But why the highlighted "ships free" on that page? Weird marketing.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: 001 on January 26, 2018, 07:23:38 pm
I`m crasy with 25 pages tread   |O

But tell me in two words please:

Is item have some big problems exept stupid power supply ground?
Is it good for money?
Why nowbody didnt rehouse it in metal enclosure with external quiet 60Hz transformer PS?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: SMB784 on January 26, 2018, 07:45:21 pm
I`m crasy with 25 pages tread   |O

But tell me in two words please:

Is item have some big problems exept stupid power supply ground?
Is it good for money?
Why nowbody didnt rehouse it in metal enclosure with external quiet 60Hz transformer PS?

1.) Is item have some big problems exept stupid power supply ground?  Yes, it has the problem that it breaks itself for no reason if you turn it on too many times (i.e. it has a very limited lifespan)
2.) Is it good for money? If the above problem is fixable, yes.  Otherwise, no.
3.) Why nowbody didnt rehouse it in metal enclosure with external quiet 60Hz transformer PS? People have done that
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 26, 2018, 07:57:16 pm
@001: To make it short for you:

The signal parameters of the generator are very good for the price IF/WHEN this thing behave according to the specification, measurements have been made with pro equipment and I've actually heard the signal in hi-end transceiver. It's very clean and stable and only on high levels on 50ohm load you start hearing the power supply and distortions. The modulation and usability is very good and the PC software control it, it's clumsy but usable. The external USB control interface looks like an ASCII command serial port, so it can be controlled from different other device. The good new end here !!!

The bad news:
The power supply is a miserable, unstabilized, ungrounded POS, and noisy under load. It leaks high voltage on the floating ground and has to be grounded and/or replaced with an stabilized +/-15V, +5V stabilized power supply, no discussion here. Ground this shitty POS PS or better replace it. This alone will increase the quality of the signal, especially under load at high levels. the output operational amplifiers could be tweaked and replaced with two independent one, same with the oscillator, could e replaced with stable external reference. This will give you some minor but useful improvements.

 THE MISERABLE BAD NEWS AND THIS IS WHY FEELTECH IS A BAD COMPANY THAT DISRESPECTS THE CUSTOMERS

As others have said, the thing has a terrible firmware flaw and it self-destroys after some power-cycles, and we're fighting and struggling either reverse or reproduce the front panel firmware, Feeltech put there some kind of "salami pricing" to differentiate models.
They WILL NEVER RELEASE AN FIRMWARE UPDATE AND IF YOU DO ANY MODIFICATION YOU EITHER HAVE TO THROW IT AWAY OR PARTICIPATE ON OUR EFFORTS HERE !!!
If you want a plug'n play generator and you're not prepared for serious efforts and frustration, buy something else, don't buy it !!!
 YOU HAVE BEEN WARNED !!!

   
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: SMB784 on January 26, 2018, 09:03:10 pm
As others have said, the thing has a terrible firmware flaw and it self-destroys after some power-cycles, and we're fighting and struggling either reverse or reproduce the front panel firmware, Feeltech put there some kind of "salami pricing" to differentiate models.

Just out of curiousity, what does "salami pricing" mean?  I've never heard the term used before.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 26, 2018, 09:27:21 pm
@SMB784: AFAIK, "salami pricing" or "salami slicing"means having a product, that have its intrinsic capabilities limited arbitrarily and then the limitations are removed after paying piecemeal, like all those scopes and analyzers and other TE that have 100% same hardware but features (sometime trivial) blocked and unlocked for extra cash, so the fully featured device it's the salami and you slice it for the customers to buy 100g at a time (only when he's starving, of course).
This proved to be a good sales and marketing strategy, because it was statistically proven that slicing the features and selling them separately brings more profit then selling the device fully featured ( for example, one scope/SA fully featured costs less than the same scope  + later bought licenses/unlock codes for the feature).
In our case, Feeltech decided copy this strategy and launched 2-3 models with the EXACT same hw, but frequency ranges limited arbitrarily (20, 30, 60MHz or such).
But but being beginners at this game, they put the limitations in the  front panel MCU firmware and because the platform has no DRM, they 've released different priced versions with the MCU flush fully locked and no possibility of upgrade.
This would have somehow worked, but their firmware is buggy as hell and crashes, corrupting the data structures of the flash, and without updates possible on-site, the salamification strategy ;) failed.

 Cheers, DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: SMB784 on January 26, 2018, 10:57:14 pm
Good explanation, I understand now.  Thanks for that clarification.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Yansi on January 26, 2018, 11:19:00 pm
Didn't know about the phrase "salami pricing", although I got  sieben Jahre Deutchkurs abgeschlossen.  :)

(Or is it a German specialty word phrase? Never heard of it.)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: ArthurDent on January 26, 2018, 11:21:29 pm
This might be considered "salami pricing". The company I used to work for made a product to read electrical power meters. They also made a reader/programmer to program these same meters. The reader sold for $3000 and the reader/programmer for $5000. I worked on this line of products so I knew the only difference was the code contained in the eprom that told the unit what to do. I asked a marketing representative how they could justify charging that big difference for basically no physical difference and he told me they were charging for functionality.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: 001 on January 27, 2018, 12:34:25 am
Sanx a lot!

What is alternative avaliable at EBAy?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 27, 2018, 10:00:11 am
Sanx a lot!

What is alternative avaliable at EBAy?

Well on need to sank me, the problem is that are really not  many acceptable AWGs in this price range, the FY6600 it's a sane design with possibilities of improvement by a hobbyist, or else nobody will give a rat behind for it.
What sinked it as a product, were the miserable decisions of FeelTech, a company that doesn't care about customers and wanted to squeeze the last cent form a good design, by Chinese-fying it.
IMHO if they would have chosen a sane power supply, with good mains isolation, suitable for a test instrument, the price increase would have been, like 10EUR, at most.
If they would have assembled the hi-quality components (the PCB has places for them) that would have added an extra 10EUR, maybe.
Adding a way to update the firmware, or at least opening the protocol to the signal board, would have not cost them a cent and all of the bad reputation would be gone, "oh well, we've screwed this firmware version, kindly please update", hell, they could have put this option in their PC control software.

But they've really wanted to sell the same hardware at different prices, and they thought that locking the firmware will protect them against the customers "upgrading" the devices and competition copying their design, that is laughable, on the chosen hardware it would have taken a week at most to a dedicated Chinese "replica laboratory" to build such a replica. But how much cheap a similar hw replica could cost, the profits on this design sold at 100EUR end price were anyway razor thin and the competition has build one rather similar device with R/2R DACs that will now slowly erode their market, even if IMHO the ADC solution is better.

They should have take a hint from their betters, Rigol and Siglent, that were not making a fuss about the enthusiasts modifying their "salami" to get all the slices ;), because they've realized that in professional environment it's not worth the time spent and loss of warranty, and if you have actual and future professionals getting used with your stuff, they will recommend it in the workplace. Microsoft realized this long time ago.

 So yeah, I can't really recommend a similar replacement, if you get the FY6600 with the 3.2 firmware, it's somehow OK (no reported catastrophic crashes), after the modification of the PS and the previously described stuff, it depends on how much you're convinced that voting with the wallet can convince a company to change it's ways.

 For me it's a nice hobby project, I've improved my old hw knowledge (too much sw dev in the day job), got reasons for a new cool project (a high performance LA), meet nice people and my inner geek had fun looking on how they implemented their stuff and trying to reverse it. And in the end, I may also got an usable AWG and signal generator out of it ;). So it's worth the money and time spent.

YMMV of course  :D

 Cheers,
 DC1MC


Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on January 27, 2018, 10:01:34 am
Hi Guillaume,
welcome to the forum .
That sounds like good news ,maybe the original supply was responsable for the dodgy batch ,
I said I might as well repost this image from a previous comment for the purposes of comparison.
not the greatest of images ,maybe theres a better one to be found .


Hi folks
(and welcome to Guillaume, the french team is growing day after day  :D)

Regarding the PSU photo you posted here, it doesn't sounds good at all imho.
The batch or the provider of the PSU seems different, but as a result it's always a holy piece of shit.
10µF as a primary cap is undersized, a 33µ or 47 value should be a minimum.
No reasonable quality highspeed diodes and low ESR capacitors on the ouptput stage, even if it costs some more cents, it would be a positive gamble for Feeltech.
Proceeding like Feeltech is doing with the PSU design is a total mistery for me.

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: 001 on January 27, 2018, 12:39:58 pm
--

thanx again!


Does it mean what firmware can fail randomly? Is it possible to dump it?
Is a firmware fail a part of Planned obsolescence strategy?
How many  bricked FY6600 You know?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 27, 2018, 05:26:17 pm
@001:
Yes, it's very possible to fail, totally random and unexpected, because FeelTech don't feel anything for its customers.

No, the firmware it's locked, there is a paper from the German Fraunhoffer Institute describing an attack against flash reading protection (with code for the exploit device), so far nobody, AFAIK, managed to do it for this chip.

No, that was a stupidly done sales strategy that backfired, the bad company FeelTech representative (that actually STARTED this thread to advertise their device !!!)  even admitted that their NEXT model will have upgrade capabilities, like somebody will pay AGAIN for their stuff, but prolly not a problem, they we'll change the company name as usually in China.

At least 4 bricked devices in this thread, mine with firmware 3.1 just destroyed so far the stored sine waveform but their latest software can attempt to repair it that, most of the people had them returned via EBAY or Amazon policies, the problem is with the people that already modified their device's power supply and lost warranty 2 weeks later. Even the persons who didn't modify the devices and had them auto-bricked had to deal with hostile and non-cooperative distributors.


@everybody else - Prepare for FUUUUUUN WITH REGISTEEEERS  in the next post !!!
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 27, 2018, 10:15:28 pm
Fun with Registers: Episode 3 "Off and On"

The CH1/2 switching procedure does two large IDENTICAL transfers (T1 and T2) and a small one that actually matters (T3)

Let's start with T3, 21 register writes.

1D:00000002
24:00000010
2B:00000A50
2C:000007FF
06:000000C4
06:000000C4
2D:00000DD1
2E:00000000
02:000186A0
01:00000000
04:000186A0
03:00000000
2F:00010000
30:00010000
05:00000020
38:07FFDFFF
39:07FFDFFF
08:000FFFFF
09:000FFFFF
37:00000001
37:00000000


This is actually the "classical" CH1/2 parameters setting, from the previous episodes you've seen that this train of registers comes when one rotates the digitizer button and change a channel parameter, it could be possible that actually this is all you need to set the parameters, at least in sine wave.

##### Commercial break >:) #####

T1 and T2 are two identical transfers of 4 identical large-patterns, they seem to be used to build the waveform displayed on the LCD by sampling 100 times the FPGA waveform RAM and also a mystery part of the RAM that could be a calibration constant.
Each large-pattern has 100 basic-patterns, or samples, the address/block from where to read is given in the register 0x12 (at least), the readback is done via register 0x0E, another register that it's read is 0x18, but it always return 32bit of 0, could be a way to prime the SPI block or maybe some status.
The RAM addresses/blocks in the register 0x12 are always spaced at the 0XA2 offsets.

The waveform samples are nice and clear, with some peculiarities (the wave first value doesn't start from 0), but the the accompanying calibraton/offset/mystery constant is vey strange, please see the plots. Please see the attached plots.


Basic-Pattern (sample) element:

12:00063F5B <- Setting the sample point address, waveform.
0F:00000001 <- Write op, unknown purpose.
0F:00000000 <- Write op, unknown purpose.
18:00000000 <- Read but result is always full 0.
0E:XXXXXXXX <- Read operation there, waveform value.
12:00063F5A <- Setting the sample point address, calibration ?
0F:00000001 <- Write op, unknown purpose.
0F:00000000 <- Write op, unknown purpose.
18:00000000 <- Read op, always 0.
0E:XXXXXXXX <- Read op, calibration constant value ?

Notes:
At the large patterns start there is a small 4 register op header, purpose unknown:
14:00000000 <- Write op, unknown purpose.
16:00000000 <- Write op, unknown purpose.
18:00000000 <- Read op, always 0
18:00000000 <- Read op, always 0

All uses data files are attached for independent verification, plots of one full waveform sample and the corresponding calibration offsets/constants are attached.
All data derived from member fremen67 capture file fy6600_CH1_OFF_ON_100Mhz_FULL.dsl form a previous message.

 Cheers and tired,
 DC1MC
 
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on January 28, 2018, 05:46:40 am
Sorry for the lack of bit bashing from me but the shack is currently over 45 degrees again  :phew:

I have ordered a bus pirate to play with this as well
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 28, 2018, 08:56:42 am
Sorry for the lack of bit bashing from me but the shack is currently over 45 degrees again  :phew:

I have ordered a bus pirate to play with this as well

@beanflying, oh the injustice of weather distribution, here in between two large rivers  I have to deal with Gothic/Gotham weather for 10 weeks now, it's a perpetual dusk and then night, when the bloody hurricane was blowing the sky cleared for 2 hours and then the ceiling closed again, it drives me crazy, there a good chance to go to a tanning salon just for the UV and vitamin D.
About your choice of LA, Bus Pirate, I kind of lost the contact with whatever community stuff, but you're sure that it can stream reliably at 50MHz at least 6 channels and has RLE in sample mode?
Or else it's useless for our SPI bus-pirating purposes on FY6600.

@fremen67 You are the savior Mua'Dib, until my LA project bears fruits you're the only one who got reliable captures, in need the following captures:
 - Setting amplitude/frequency message (start capture, trigger on -CS and rotate the encoder one position), it seem that the setting message on 3.2 has 21 register operations instead of 20 and I want to see the difference. It will help with the Episode 2- "Hopey and changey!
 - The same setting message for duty cycle value when the wave it's square, to activate this function, the duty cycle register it's assumed but not proved, kindly please try to get the extremes and somwhere in the middle.
 - BIG ONE: Capture the process process of switching the wave, form sine to triangle, and triangle to square, if's the only big deal on how to load waveforms, there is also the custom waveform issue but we leave this for later.
Thanks a lot and sorry that I put this burden on you, for the moment no other capable LA is hooked to an 3.2FY6600, made by FeelTech - "Our Bugs it's Your Problem".


@everybody - I'm going to tackle the startup sequence, wish me luck, 'cause it's looking a lot like work !!!
 
 Cheers,
 DC1MC
 


Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: texaspyro on January 28, 2018, 07:06:32 pm
You REALLY don't want to be using a logic analyzer that samples the signals asynchronously.  You want one where the data lines are clocked in by the SPI clock (preferably qualified by chip select).  That way you only transfer data that is relevant and at a 18 MHz max data rate. 

If you have an analyzer with enough channels, maybe build a shift register front end and clock the whole (48-bit?) transfer into it and have the analyzer grab those.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 28, 2018, 07:27:14 pm
You REALLY don't want to be using a logic analyzer that samples the signals asynchronously.  You want one where the data lines are clocked in by the SPI clock (preferably qualified by chip select).  That way you only transfer data that is relevant and at a 18 MHz max data rate. 

If you have an analyzer with enough channels, maybe build a shift register front end and clock the whole (48-bit?) transfer into it and have the analyzer grab those.

In theory it works, in practice not so much, we need here the temporal information as well and unfortunately not all the operations are 3 x16bits over one CS low, the read transfers are first transfer register address follower by one or more 2x16bits per CS low value read operations. So IMHO, no way around a good minimum 50MHz sampling, RLE and streaming LA.

But if you have the FY6600, you can give it a try and post some captures, I will decode them for you, start with short message, like value changes that are just 20-21 register operations.

 Cheers,
 DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: texaspyro on January 28, 2018, 09:47:43 pm
For the protocol decoding, I doubt you need any temporal data.   You just need the data that is transferred.  Also, you could use just an 8-bit shift register... that would cut the data rate down quite a bit.  I've been using logic analyzers and protocol decoding for over 40 years.  Unless there is something silly going on with the FY6600,  using an asynchronous capture mode is the wrong way of going about it.

I don't have a FY6600 to test, or time to do it if I had one.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 29, 2018, 06:37:30 pm
Hello everybody, quick update for the startup sequence, it mostly consists of endless reads, WITHOUT sending an address, the readback values are some times a string off zeros or a string of 0x00000001.

Fremen67, guys, you're still around, not much activity over WE :(.

 Cheers,
 DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on January 29, 2018, 08:24:36 pm
The unit is finally in Holland. So yes pretty quiet :D Need it on the doorstep....
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: gbraux on January 29, 2018, 10:05:57 pm
Hi. I am new to the forum, so a big hello from Paris, France.

I have just received my FY6600 (30Mhz) from Aliexpress and ... looks like they have updated the PSU :-)
I also ordered some IEC connectors at the same time ... but I won't bother making the ground hack : Ground-BNC to Ground-Earth = 300mV :-)

Did you measure AC or DC?

Oups ! My bad, was measuring DC ... now measuring 84V AC  :-(
Just added an IEC plug (and as the ground connector is not there anymore on the refreshed PSU, I directly soldered earth-ground to the back of the PCB).
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on January 29, 2018, 10:13:28 pm
I think my SB may windup inside the GDS-2072E  Just need the proper signals and a map of the state machine.  Integrating it with the GDS-2000E software is more work, but preferable in the long run.  One could do a lot of cool stuff with the addition of a GPSDO timebase.  Full measurement  up to 6 M for under $400?  Not bad.  But I think I'll buy a JDS for regular use unless someone comes up with a way to reflash the FT devices with a usable image.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on January 29, 2018, 10:20:37 pm
Fremen67, guys, you're still around, not much activity over WE :(.
Well this is not exactly what I would say.

I decided this Saturday evening to have a one hour session on the FP-FPGA protocol decoding to see what I could find. What happened to me was worse than being attracted by a black hole. My last two evenings where long… my last to nights were short. This thing is more addictive than drugs.
First I decided to add the nor flash into the game. Cybermaus already explained precisely how it was organized, containing the predefined waveforms and the arbitrary waveforms as well. As I did a backup of the flash, I already had the header pins soldered. A quick check at the Flash_CLK pin showed that it was running @ 20Mhz. So definitely a separated SPI bus that has to be connected to the FPGA. Five pins connected later, and after adding a second SPI protocol in the LA configuration, I was able to see the flash talking synchronized with the FPGA-FP telegrams when switching waveforms. So far so good. But that was just the beginning of the black hole thing… Long story short..The service telegrams are now decoded  (containing mode, state, setpoints of CH1&CH2) and the Read mechanism from Flash to FPGA, From Flash to FP and Write from FP to Flash is now clear, that is:
1-   Direct transfer requests of waveforms from Flash to FPGA (FP don’t see the values)
2-   Read requests from flash to FP, FPGA being a letter box
3-   Write requests from FP to flash, FPGA being again a letter box (when using the PC software)

All the captures I made showed a combination of those mechanisms in Power On, ON/OFF, waveform selection, setpoint modification telegrams.
There is also a specific telegram when in Measure Mode but it is much simpler and smaller, for reading counter, frequency and the 2 half parts of a cyclic input signal.
You will find attached a description overview of the registers, new ones, some of them still to be identified, others already identified by DC1MC who also already explained the register write mechanism.
With this file, every one should be able to decode almost all the messages that we captured. The main missing registers are used during the power ON sequence, I suppose for initialization purposes but no clue for them at the moment.

I will post some other documents later on too that might help understanding the mechanism and will also try to explain more precisely the read/write protocol.
Not sure how long I will stay awaken ...
Enjoy!

Hello everybody, quick update for the startup sequence, it mostly consists of endless reads, WITHOUT sending an address, the readback values are some times a string off zeros or a string of 0x00000001.
Should be crystal clear now... :)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: SMB784 on January 29, 2018, 11:54:16 pm
Fremen67, guys, you're still around, not much activity over WE :(.
Well this is not exactly what I would say.

I decided this Saturday evening to have a one hour session on the FP-FPGA protocol decoding to see what I could find. What happened to me was worse than being attracted by a black hole. My last two evenings where long… my last to nights were short. This thing is more addictive than drugs.
First I decided to add the nor flash into the game. Cybermaus already explained precisely how it was organized, containing the predefined waveforms and the arbitrary waveforms as well. As I did a backup of the flash, I already had the header pins soldered. A quick check at the Flash_CLK pin showed that it was running @ 20Mhz. So definitely a separated SPI bus that has to be connected to the FPGA. Five pins connected later, and after adding a second SPI protocol in the LA configuration, I was able to see the flash talking synchronized with the FPGA-FP telegrams when switching waveforms. So far so good. But that was just the beginning of the black hole thing… Long story short..The service telegrams are now decoded  (containing mode, state, setpoints of CH1&CH2) and the Read mechanism from Flash to FPGA, From Flash to FP and Write from FP to Flash is now clear, that is:
1-   Direct transfer requests of waveforms from Flash to FPGA (FP don’t see the values)
2-   Read requests from flash to FP, FPGA being a letter box
3-   Write requests from FP to flash, FPGA being again a letter box (when using the PC software)

All the captures I made showed a combination of those mechanisms in Power On, ON/OFF, waveform selection, setpoint modification telegrams.
There is also a specific telegram when in Measure Mode but it is much simpler and smaller, for reading counter, frequency and the 2 half parts of a cyclic input signal.
You will find attached a description overview of the registers, new ones, some of them still to be identified, others already identified by DC1MC who also already explained the register write mechanism.
With this file, every one should be able to decode almost all the messages that we captured. The main missing registers are used during the power ON sequence, I suppose for initialization purposes but no clue for them at the moment.

I will post some other documents later on too that might help understanding the mechanism and will also try to explain more precisely the read/write protocol.
Not sure how long I will stay awaken ...
Enjoy!

Hello everybody, quick update for the startup sequence, it mostly consists of endless reads, WITHOUT sending an address, the readback values are some times a string off zeros or a string of 0x00000001.
Should be crystal clear now... :)

That is some excellent work there, Fremen!

I just got my device in the mail today, and I just found out that it is version 3.1.

With that being said, in light of Fremen67's work, can we get an update on what still needs to be done?  What tasks are left, and what unknowns still exist?  I would like to contribute, but I don't yet know what I should be doing.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on January 30, 2018, 12:50:43 am
With that being said, in light of Fremen67's work, can we get an update on what still needs to be done?  What tasks are left, and what unknowns still exist?  I would like to contribute, but I don't yet know what I should be doing.

There are still some registers to discover (I just realized I forgot to update my document with Reg 0x37... for the next time).

Registers definition are the keys to understand what is done on a macroscopic point of view. To move on, we need now to have a macroscopic description of what is done by the FP for each possible action on the FP.

A macroscopic description would be: "When changing the frequency on a sine wave, the FP sends a service telegram which includes: modulation status , CH1&CH2 offsets, ..." rather than: "When changing the frequency on a sine wave, the FP writes reg0x1D, Reg0x24, Reg0x2B, Reg0x2C, ...."

Another example: If you select a new Sine waveform, you could describe it this way:
"The FP:
1 - Reads CH2 waveform from flash
2 - Reads CH1 Waveform from flash
3 - Wait about 58ms
4 - Sends a service telegram with modulation status, ...
5 - Request the FPGA to read a sine waveform from the Flash
6 - Sends a service telegram with output status, ..."

This would the base for a new FP program.


Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on January 30, 2018, 01:14:33 am
@DC1MC
You will find attached the files you requested (plus some extra).
For the waveform loading captures on CH1, I selected ARB63 on CH2. This is an empty waveform, which eases the analysis (you will notice with MISO from FP SPI). It  is also stored in Flash so you will see CH2 transfer).

There is definitively something strange with the TRGL waveform :
- When switching from DC to Triangle, The FP reads CH2 waveform, than CH1 waveform (that is TRGL) from flash but does not request FPGA to update its waveform from flash
- When switching from Ramp to Triangle, The FP reads CH2 waveform, than CH1 waveform (that is TRGL) from flash AND does request FPGA to update its waveform from flash (you see the transfert)

I wonder if it's a new behaviour on v3.2 or if it's already like that on V3.1 ...

The other waveform loading captures also show which are in flash and which are not.

The duty cycle modifications on a square waveforms look very interesting!

Good luck. You will see that the flash SPI under the other signals will change your live  ;)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 30, 2018, 08:34:45 am
Fremen67, guys, you're still around, not much activity over WE :(.
Well this is not exactly what I would say.

I decided this Saturday evening to have a one hour session on the FP-FPGA protocol decoding to see what I could find. What happened to me was worse than being attracted by a black hole. My last two evenings where long… my last to nights were short. This thing is more addictive than drugs.
First I decided to add the nor flash into the game. Cybermaus already explained precisely how it was organized, containing the predefined waveforms and the arbitrary waveforms as well. As I did a backup of the flash, I already had the header pins soldered. A quick check at the Flash_CLK pin showed that it was running @ 20Mhz. So definitely a separated SPI bus that has to be connected to the FPGA. Five pins connected later, and after adding a second SPI protocol in the LA configuration, I was able to see the flash talking synchronized with the FPGA-FP telegrams when switching waveforms. So far so good. But that was just the beginning of the black hole thing… Long story short..The service telegrams are now decoded  (containing mode, state, setpoints of CH1&CH2) and the Read mechanism from Flash to FPGA, From Flash to FP and Write from FP to Flash is now clear, that is:
1-   Direct transfer requests of waveforms from Flash to FPGA (FP don’t see the values)
2-   Read requests from flash to FP, FPGA being a letter box
3-   Write requests from FP to flash, FPGA being again a letter box (when using the PC software)

All the captures I made showed a combination of those mechanisms in Power On, ON/OFF, waveform selection, setpoint modification telegrams.
There is also a specific telegram when in Measure Mode but it is much simpler and smaller, for reading counter, frequency and the 2 half parts of a cyclic input signal.
You will find attached a description overview of the registers, new ones, some of them still to be identified, others already identified by DC1MC who also already explained the register write mechanism.
With this file, every one should be able to decode almost all the messages that we captured. The main missing registers are used during the power ON sequence, I suppose for initialization purposes but no clue for them at the moment.

I will post some other documents later on too that might help understanding the mechanism and will also try to explain more precisely the read/write protocol.
Not sure how long I will stay awaken ...
Enjoy!

Hello everybody, quick update for the startup sequence, it mostly consists of endless reads, WITHOUT sending an address, the readback values are some times a string off zeros or a string of 0x00000001.
Should be crystal clear now... :)

Holly rotating cow on 3D gymball, fremen67 are you a younger version of me  ^-^ ?!?!  I remember ca 35 years ago disassembling the Sinclair Spectrum ROM with just a pencil, a paper notebook and bootleg copy of Z80 manual. Painful, but somehow you wake up  in an excellent mood, better than the other thing ;)

That's a real effort here people, the WE silence was bringing us so much stuff, thank you so much, chapeau bas  ;D. I was coming very late yesterday from the Arbeit, and only this morning I had a look at the headmounted glasses post responses, and observed that  there is one more post in the FY6600 topic and casually looked on it, and by Jove, now I have to take  some hours off !!!

One quick thing about the register 0x25 (50 million) and 0x26 (500million), they seem to be correlated with the 50MHz oscillator that is used as timebase, in a joyful future we may be able to replace it with a stable 10MHz source, and if these are the only modifications, jackpot  >:D !!!  Most likely they are just time base for the frequency measurement, but one can dream :).

I would look in to the triang waveform, can you switch sometime form sine to triang, to see it this time at least it updates the waveform in RAM, or it could be as well yet another bug from our FeeTech guys.

The common measurement along with the flash SPI was really perfect, we need to see edges, where this shitty fw screws thing. I'm really curious where in the MCU firmware are writing operations, because I can understand screwing up the external flash, but I don't understand what had happened with the internal one ?!?!?

What we need now:

 - Blue pills board to do a quick serial-to-SPI converter, I'm curious if the Dupont pins are fitting there, then there is no need for connector.
 - A set of basic routines, I'll list them there for reference:
 = Wait_For_Ready.
 = Writer_register
 = Set_Register_Address
 = Read_Register
 
And then one level higher routines:
 Set_Freq
 Set_Level
 Set_Offset
 Set_Phase
 ---
 and so on
(for the development purposes, these can be emuleted for the moment in a PC program that discuss with the blue pill via serial)

And of course the telegrams ( I like this word, better thane the messages that I was using)


If we get some good news form the members that promised to extract the schematic, we can focus afterwards on how the LCD is driven and see if in the yuuuge library collection from STM there is something compatible, and get rid of the ugly fonts  :box:.

Also in the end ( I have now to run ), it would be sooo nice to have a member with a 30MHz or lower device, trying to program the 59.999 MHz :), revenge at last  >:D

 Cheers,
 DC1MC



Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on January 30, 2018, 11:39:46 pm
Holly rotating cow on 3D gymball, fremen67 are you a younger version of me  ^-^ ?!?!  I remember ca 35 years ago disassembling the Sinclair Spectrum ROM with just a pencil, a paper notebook and bootleg copy of Z80 manual. Painful, but somehow you wake up  in an excellent mood, better than the other thing ;)
Younger ... well... as I also remember having done the same kind of stuff on the ZX81 (the model before the Spectrum) in 1981, that is ca 37 years ago, (and I also had the same tools  ;D) you could also be the younger one  ;)
I am pretty sure that I still have the ZX81 with the original manual and some tapes somewhere in the attic...

I would look in to the triang waveform, can you switch sometime form sine to triang, to see it this time at least it updates the waveform in RAM, or it could be as well yet another bug from our FeeTech guys.
No problem when switching directly from Sine to Triangle, it updates the waveform in RAM.

What we need now:

 - Blue pills board to do a quick serial-to-SPI converter, I'm curious if the Dupont pins are fitting there, then there is no need for connector.
 - A set of basic routines, I'll list them there for reference:
 = Wait_For_Ready.
 = Writer_register
 = Set_Register_Address
 = Read_Register
 
And then one level higher routines:
 Set_Freq
 Set_Level
 Set_Offset
 Set_Phase
 ---
 and so on
(for the development purposes, these can be emuleted for the moment in a PC program that discuss with the blue pill via serial)
I have a STM32 dev board that I used some years ago. It may even be the same CPU as the FP. I will hock it and try to send some SPI commands. I would like to check the read sequence with CS RS. I will try with Reg0x18 (cyclic flash status update) as it seems to be the easier to begin with.

Cheers!
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on January 31, 2018, 07:33:15 am
@fremen67 OK then, I'm the low energy youngster then  :-DD.

Nice work with the triangle wave, then it's yet another bug form FeelTech.
I'm also wondering if those really insane repetitions are really needed, the endless repetitions of all the parameters for the slightest change and so on, I have a feeling that the SB programming can be streamlined a lot, this we'll also help if we're gonna improve the seeping function.

What can I say, I'm humbled, keep up the good work, if you'll be able to communicate with the SB you'll be our hero, I  came so drained form the day job and this endless gray sky it's sapping the rest of the what little energy remains :(. But I'll push myself to see this to the end.

 Cheers,
 DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on February 01, 2018, 01:29:21 am
Quick update of preliminary service telegram tests:

I hooked up a STM32 dev board directly to the Signal board on the FY6600 and was able to change frequency and amplitude  :-+

That is just a proof of concept but this is very encouraging.
The test was as follows:
- FY6600 powered on, CH1 ON and connected to a scope, sine @10Khz and 5V amplitude, LA still connected
- I disconnected the ribbon  from the FP and connected directly my dev board to it
- I downloaded the first test program to the dev board: service telegram with modified frequency @20Khz and ... bingo! 20khz on the scope.
- Second test with a modified Amplitude à 2.5V and bingo again !! 2.5V Amp on the scope.
Attached a photo of the setup, 2 functions of the test program and the first LA capture of an alien processor fooling the FPGA 8)
I think I will sleep well  8)

Code: [Select]
void test_service_telegram(void)
{
  fpga_write_register(0x1D,0x00,0x02);
  fpga_write_register(0x24,0x00,0x10);
 
  fpga_write_register(0x2B,0x00,0x7FF);
  fpga_write_register(0x2C,0x00,0x7FF);

  fpga_write_register(0x06,0x00,0x80);
  fpga_write_register(0x06,0x00,0x80);

  fpga_write_register(0x2D,0x00,0xE65); // 5.00V
//  fpga_write_register(0x2D,0x00,0x732); // 2.50V
  fpga_write_register(0x2E,0x00,0x00);

//  fpga_write_register(0x02,0x03,0x0D40); // 20kHz
  fpga_write_register(0x02,0x01,0x86A0); // 10Khz
  fpga_write_register(0x01,0x00,0x00);
  fpga_write_register(0x04,0x01,0x86A0);
  fpga_write_register(0x03,0x00,0x00);
 
  fpga_write_register(0x2F,0x01,0x00);
  fpga_write_register(0x30,0x01,0x00);

  fpga_write_register(0x05,0x00,0x20);
  fpga_write_register(0x38,0x7FF,0xDFFF);
  fpga_write_register(0x39,0x7FF,0xDFFF);

  fpga_write_register(0x08,0x0F,0xFFFF);
  fpga_write_register(0x09,0x0F,0xFFFF);
  fpga_write_register(0x37,0x00,0x01);
  fpga_write_register(0x37,0x00,0x00);


static void fpga_write_register(uint16_t chRegister, uint16_t chDataMSW, uint16_t chDataLSW)
{
  __FPGA_DC_CLR();
  __FPGA_CS_CLR();
  __FPGA_WRITE_WORD(chRegister);
  __FPGA_DC_SET();

  __FPGA_WRITE_WORD(chDataMSW);
  __FPGA_WRITE_WORD(chDataLSW);

  __FPGA_CS_SET();


Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on February 01, 2018, 05:18:59 am
Cant seem to remember front side shots of the FP. Wonder what K8 did? Wonder also what chip is hiding on the lcd......

Switch is connected to PB6 on the STM btw :-\
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 01, 2018, 06:45:31 am
@fremen67 great news, nice effort. Looking good so far.

I think the LCD is a standard ILI9340/ILI9341 chip one. These are used very widely. Libraries are no issue for these.

My unit is available for pickup today, hope to get some schematics done next week.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on February 01, 2018, 06:59:07 am
Forgot to add my FP PCB was 'packed' with two washers to allow a couple of the switches to not be closed when the nuts were done up  properly :--

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Diabolo on February 01, 2018, 06:59:52 am
Hello,

The K8 switch has the same function when the rotary encoder button is pressed.
Feeltech deliberately destroyed the K8 switch to prevent deformation of the facade.

Diabolo
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on February 01, 2018, 07:02:23 am
@fremen67 you're our hero, you deserve a good rest, better than this can't be.

Now I'm wondering two things:

 1) Is it really necessary to send a full telegram to change one parameter, what about just sending the SetFrequecy sequence and see if just the frequency changes ? If we can send the parameters individually, that will make a kick-ass sweeping generator /wobbler/antenna analyzer  8).

 2) What about programming 65.200MHz, what it's actually the upper limit of the sine wave, hopefully someone with a 30MHz unit will chime-in and try to program 69MHz on it, if it works I have a feeling that the 30MHz cheaper ones will disappear abruptly  >:D.

 Best regards,
 DC1MC

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on February 01, 2018, 07:39:53 am
I think the LCD is a standard ILI9340/ILI9341 chip one. These are used very widely. Libraries are no issue for these.
Yes that is also my first bet. It definitively has to be widely spread ans cheap. Once the FP schematic is ready, this should be easy to check.
If it's not the ILI9341, there won't be a lot more to check.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on February 01, 2018, 07:47:10 am
1) Is it really necessary to send a full telegram to change one parameter, what about just sending the SetFrequecy sequence and see if just the frequency changes ? If we can send the parameters individually, that will make a kick-ass sweeping generator /wobbler/antenna analyzer  8).

 2) What about programming 65.200MHz, what it's actually the upper limit of the sine wave, hopefully someone with a 30MHz unit will chime-in and try to program 69MHz on it, if it works I have a feeling that the 30MHz cheaper ones will disappear abruptly  >:D.

This will be very easy to check but I first have to code the initialization sequence in the dev board because switching the SB from FP to dev board when everything is powered ON is really not the way to go .
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 01, 2018, 08:27:02 pm
Always nice having a new unit to play with and it stops with a Feeltech logo at boot (Feelbad)

Then off course opening the unit to plug in the FPGA ribbon connector and everything is Feelgood. Strange quality control these guys have :(

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Specmaster on February 01, 2018, 09:25:59 pm
Always nice having a new unit to play with and it stops with a Feeltech logo at boot (Feelbad)

Then off course opening the unit to plug in the FPGA ribbon connector and everything is Feelgood. Strange quality control these guys have :(
Well it passed the test bench OK, whats the matter with that? It just took the quicker route to you by bypassing the tester  :-DD
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: beanflying on February 01, 2018, 10:23:27 pm
Always nice having a new unit to play with and it stops with a Feeltech logo at boot (Feelbad)

Then off course opening the unit to plug in the FPGA ribbon connector and everything is Feelgood. Strange quality control these guys have :(

Very thoughtful of them. Just getting it ready for you to start adding jumpers for hacking   :palm:
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 02, 2018, 08:39:34 am
How long were you staring at that logo feeling increasingly :scared: before you opened the device?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 02, 2018, 08:45:33 am
How about 1.5s.... saying "sukkels" and grabbed the cordless screwdriver :D
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on February 02, 2018, 12:46:04 pm
Cheapest FY6600-15MHz https://www.ebay.de/itm/FY6600-Dual-Kanal-DDS-Signalquelle-Arbitrarsignal-Signalgenerator-15-60MHz-mj/311950831692 (https://www.ebay.de/itm/FY6600-Dual-Kanal-DDS-Signalquelle-Arbitrarsignal-Signalgenerator-15-60MHz-mj/311950831692)

 Can it be upgraded  >:D ?

 Cheers,
 DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 02, 2018, 03:10:42 pm
Once your effort to write your own firmware works, I am pretty sure yes, it can.
Equally sure that at soon after that moment the 15MHz model will no longer be sold though.

Sorry for not being active myself. Still have the intent to work on the frauenhofer hack, even though it is for the wrong chip.
But a bit busy with my dayjob at the moment. I admire your (plural) progress though.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Diabolo on February 02, 2018, 04:42:48 pm
Hello,

With GPSDO 10 Mhz the accuracy of the counter measurement FY2300H is + 95hz, displayed 10.000.095 Mhz


Diabolo
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: odo on February 02, 2018, 11:57:47 pm
I am thinking about buying this generator. I like the number of features of this generator for such low price, but I see one disadvantage, maybe you could help me.
I initially decided to buy JSD6600 from FeelTech competitors, they have nice looking rubber buttons on the front panel like typical bench equipment. I expect that using "foil" buttons like on FY6600 it is not so convenient as using real rubber buttons. Could you say something about this? Are they hard to use on the table? Do generator moves when you try to press buttons?

One more questions to FeelTech representative who was on the forum, I hope is still there. Do you plan to upgrade FY6600 to rubber buttons?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DaveR on February 03, 2018, 12:18:03 am
Hi odo,

The buttons are not as bad to use as you'd think - you just need to put your fingers on top of the case and use your thumb to press them.  Yes, the case moves around, but that's because it's so light - it would still move around if it had any other type of buttons.  Either put something behind it, or put some sticky, non-slip rubber feet on the bottom of the case to hold it a little better (or add some weight inside, like a big power transformer).
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 03, 2018, 01:32:12 pm
Any body in Europe or otherwise (shipping :() who is willing to send their bricked unit or front panel to me for software testing?

I like to keep my unit working for comparison of features while testing out all functions. Will send it back when wanted or needed or when the software is up to par.
Paying €70 for a 15Mhz unit is a bit of waste in my opinion.

I finished the the reverse engineering of the front panel of my unit, just need to draw the schematics in some tool. Eagle is what I use normally for these tiny schematics.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: CharlieEcho on February 03, 2018, 01:47:07 pm
Either put something behind it, or put some sticky, non-slip rubber feet on the bottom of the case to hold it a little better (or add some weight inside, like a big power transformer).

Some kind of little chock secured to the shelf or desktop behind it's front feet (underneath the unit) works too.

The membrane buttons are fine in terms of feel (although they're less durable). The encoder wheel is clicky.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: bitseeker on February 04, 2018, 02:08:11 am
I am thinking about buying this generator. I like the number of features of this generator for such low price, but I see one disadvantage, maybe you could help me.
I initially decided to buy JSD6600 from FeelTech competitors, they have nice looking rubber buttons on the front panel like typical bench equipment. I expect that using "foil" buttons like on FY6600 it is not so convenient as using real rubber buttons. Could you say something about this? Are they hard to use on the table? Do generator moves when you try to press buttons?

Hi odo. Welcome to the forum.

There is another disadvantage — one that could totally outweigh your button concern. If you read back some pages from here, you'll see that this generator could lose its mind unexpectedly, rendering the device inoperative. That's what all the reverse engineering discussion is about.

So, you may want to wait and see how the brave adventurers here tackle that challenge before spending your money.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: plb on February 04, 2018, 02:47:18 am
There is another disadvantage — one that could totally outweigh your button concern. If you read back some pages from here, you'll see that this generator could lose its mind unexpectedly, rendering the device inoperative. That's what all the reverse engineering discussion is about.

...Except that V3.2, the version currently being delivered from higher turnover sources, does not seem to show this problem.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: 4thDoctorWhoFan on February 04, 2018, 02:53:54 am
Hello,

With GPSDO 10 Mhz the accuracy of the counter measurement FY2300H is + 95hz, displayed 10.000.095 Mhz


Diabolo
Well, that's horrible.  Why even bother?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: bitseeker on February 04, 2018, 02:58:22 am
There is another disadvantage — one that could totally outweigh your button concern. If you read back some pages from here, you'll see that this generator could lose its mind unexpectedly, rendering the device inoperative. That's what all the reverse engineering discussion is about.

...Except that V3.2, the version currently being delivered from higher turnover sources, does not seem to show this problem.

Yep. Just have to ensure that you can get that specific version. I don't know how many vendors know enough to send the right one.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: CharlieEcho on February 04, 2018, 04:27:42 am
95hz, displayed 10.000.095 Mhz

With the FW my unit was delivered with (3.2), clicking the encoder wheel with the selector on the frequency line (F1) changes the units between HZ, KHz, MHz, and uHz. In case anyone hasn't noticed that.

Anyone know how to change the modes the channels default to at power up? I don't really want both channels on and cranking out a ton of volts.

EDIT: Well, I don't know what I did but now I have mine starting up with the channels off, so good enough.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: plb on February 04, 2018, 05:02:49 am
If you haven't already got one, you can get a user manual from
https://kenswu.zzvps.com/Function/Manual/FY6600%20Series%20Users%20Manual%20V2.2.pdf
I sometimes find that reading it beats thumping the front panel and swearing...
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: g0mgx on February 04, 2018, 07:01:59 am
Any body in Europe or otherwise (shipping :() who is willing to send their bricked unit or front panel to me for software testing?

I like to keep my unit working for comparison of features while testing out all functions. Will send it back when wanted or needed or when the software is up to par.
Paying €70 for a 15Mhz unit is a bit of waste in my opinion.

I finished the the reverse engineering of the front panel of my unit, just need to draw the schematics in some tool. Eagle is what I use normally for these tiny schematics.

Mine isn't bricked but is definitely doing more weird things than others; I still think some of the relays are bad.

You are welcome to my unit - where are you?

Mark
G0MGX
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 04, 2018, 07:54:57 am
Any body in Europe or otherwise (shipping :() who is willing to send their bricked unit or front panel to me for software testing?

I like to keep my unit working for comparison of features while testing out all functions. Will send it back when wanted or needed or when the software is up to par.
Paying €70 for a 15Mhz unit is a bit of waste in my opinion.

I finished the the reverse engineering of the front panel of my unit, just need to draw the schematics in some tool. Eagle is what I use normally for these tiny schematics.

Mine isn't bricked but is definitely doing more weird things than others; I still think some of the relays are bad.

You are welcome to my unit - where are you?

Mark
G0MGX

Great Mark, sounds fine to me. I'm in the Netherlands. Could you check out the shipping? I'm fine with the slowboat shipping method.
Should we take it further in PM's?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 04, 2018, 12:56:52 pm
With the FW my unit was delivered with (3.2), clicking the encoder wheel with the selector on the frequency line (F1) changes the units between HZ, KHz, MHz, and uHz. In case anyone hasn't noticed that.
I had not noticed that, thanks, I do not like that standard KHz readout, and once I was stuck on uHz readout. 10000000000000uHz :palm:
Quote
Anyone know how to change the modes the channels default to at power up? I don't really wagood enough.
In the SYS->MORE menu, there is a "boot" for CH1 and CH2.
I have mine set to not start automatically also.

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cdev on February 04, 2018, 01:48:13 pm
You guys should scour the old posts here, looking for promises that I vaguely remember were made that the next version they were working on would have user upgradeable firmware.

I own the next lower version, the FY3224.

It has some issues. The very very low frequencies displayed are non-accurate. It would be nice if that could be fixed.

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on February 04, 2018, 01:53:32 pm
The vague and never followed up promises were made for the next hardware version, if will ever show up, of course that was just a marketing droid that since then never posted anything more.
The current ones will be for ever not upgradeable by the manufacturer, until a new firmware (and hope ;) ) emerge.

 So start contributing for your version with stuff, schematics, connector pins mapping, even testing the existing commands.

 Cheers,
 DC1MC
 
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: ArthurDent on February 04, 2018, 02:46:42 pm
Reply #671 gives a link to a user manual for the FY6600 but that manual is V2.2 from July, 2017 and the FeelTech home page has what appears to be the latest v2.9 from August, 2017. The date on the download link for the FY6600 English manual says 2017-10-17. 

http://en.feeltech.net/index.php?case=archive&act=list&catid=6 (http://en.feeltech.net/index.php?case=archive&act=list&catid=6)

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on February 04, 2018, 04:05:33 pm
Im still waiting on my unit to arrive .

For the purposes of experimentation and learning Ive also sent out for one of the DSO138's , contains a similar STM32 type controler chip to the FY .There is open source software available for the DSO which allows you to access an extra  analog input and two digital logic inputs on that board,  and also  a few mods to reduce the very noisey input stage . its also a simple matter to add a rotary  encoder

https://github.com/ardyesp/DLO-138

Seeing as its mostly audio I do , this unit will make a handy tool to have  for a mobile test up.
I bought a second spare perspex case and I intend to house a battery/chg ,proper analog +- rails ,and a discrete op amp based 2nd analog audio mic/line input.

Could  a dso130 board be used as a controller for the FY6600 main board ?
only the software and the push buttons would need to be added .
It seems from what ive read that we can control the main board of the FY6600 remotely with the correct usb interface .
Would it make sense to try and figure out a way to make a cheap new front panel  or how about replacing the controller chip on the FY front panel with whats on the DSO board ,then putting together our own software interface ,what about the JTS  front panel code it looks very similar too

Anyway there my ideas ,hopefully theres inspiration in there somewhere to get the ball rolling again .
 

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: CharlieEcho on February 04, 2018, 04:19:36 pm
I am happy to perform whatever stepwise procedures I can on my unit, to the extent that will help out. The STM32 attack paper (https://www.usenix.org/system/files/conference/woot17/woot17-paper-obermaier.pdf) is interesting reading but I lack the skill to have much hope of implementing the authors' "cold boot" attack on my own.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: skander36 on February 04, 2018, 06:15:56 pm
Hi guys , I am also waiting for my FY 6600 .
I have found this thread shortly after I was pay for this , so ...too late .

@DerKammi did you have paid custom tax for your ? I was ordered through Banggood .

For a new control board this ready made solutions can short time or at least may help :

https://www.embedded-wizard.de/high-performance-gui-hmi-for-stm32f7-discovery.html (https://www.embedded-wizard.de/high-performance-gui-hmi-for-stm32f7-discovery.html)
With the demo version you can compile a working interface that can be uploaded to STM board .

They have even a demo of a signal generator interface here :
https://www.embedded-wizard.de/files/cto_layout/img/demo/webgl/WaveformGenerator/EmWiApp.html (https://www.embedded-wizard.de/files/cto_layout/img/demo/webgl/WaveformGenerator/EmWiApp.html) 

Or Nextion smart displays which can send commands through Serial interface
https://nextion.itead.cc/ (https://nextion.itead.cc/) - This has free IDE and serial communication .

Many appreciations about your great work !
 

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cdev on February 04, 2018, 08:25:02 pm
Maybe you should try to get refunds on your FY6600s.

Unless I'm getting something wrong, I'm gathering that ones that are working could self destruct at any time?

Do I have this right? Does its firmware corrupt itself?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DaveR on February 04, 2018, 08:36:32 pm
Reply #671 gives a link to a user manual for the FY6600 but that manual is V2.2 from July, 2017 and the FeelTech home page has what appears to be the latest v2.9 from August, 2017. The date on the download link for the FY6600 English manual says 2017-10-17. 

http://en.feeltech.net/index.php?case=archive&act=list&catid=6 (http://en.feeltech.net/index.php?case=archive&act=list&catid=6)

The PC control software is now also up to v5.5 (may be worth trying the repair_sine option again?), and other documents include detailed descriptions of the PC -> Device serial communication and arbitrary waveform data transfer protocols, which might come in useful.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 05, 2018, 06:59:34 am
Hi guys , I am also waiting for my FY 6600 .
I have found this thread shortly after I was pay for this , so ...too late .

@DerKammi did you have paid custom tax for your ? I was ordered through Banggood .

For a new control board this ready made solutions can short time or at least may help :

https://www.embedded-wizard.de/high-performance-gui-hmi-for-stm32f7-discovery.html (https://www.embedded-wizard.de/high-performance-gui-hmi-for-stm32f7-discovery.html)
With the demo version you can compile a working interface that can be uploaded to STM board .

They have even a demo of a signal generator interface here :
https://www.embedded-wizard.de/files/cto_layout/img/demo/webgl/WaveformGenerator/EmWiApp.html (https://www.embedded-wizard.de/files/cto_layout/img/demo/webgl/WaveformGenerator/EmWiApp.html) 

Or Nextion smart displays which can send commands through Serial interface
https://nextion.itead.cc/ (https://nextion.itead.cc/) - This has free IDE and serial communication .

Many appreciations about your great work !

I did not have to pay any tax, but that is just lucky these days due to the huge amount of packages bought by the dutch these days from China. I ordered mine from Aliexpress though.

The board you linked is a F7 board, this one has huge amount of power compared to the F1 series, can't compare at all. So fancy smooth fading GUIs are possibly not all that easy on 320x240 screens.
I'm receiving the unit from Mark to develop/test the software on, so I can make his mangled unit better :D

Maybe you should try to get refunds on your FY6600s.

Unless I'm getting something wrong, I'm gathering that ones that are working could self destruct at any time?

Do I have this right? Does its firmware corrupt itself?

The story goes in this topic that V3.1 and earlier firmware corrupt them selves randomly. The V3.2 unit up until now are OK.

I am happy to perform whatever stepwise procedures I can on my unit, to the extent that will help out. The STM32 attack paper (https://www.usenix.org/system/files/conference/woot17/woot17-paper-obermaier.pdf) is interesting reading but I lack the skill to have much hope of implementing the authors' "cold boot" attack on my own.

I ordered 4 F103 boards with the same controller from Aliexpress to controll the FPGA in simple mode but also try to hack the fuse bits with the document. Hack one the other :)

Plenty to do, and also fixing to pinball machines. These projects are not helping each other.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 05, 2018, 08:41:35 am
By luck, I also did not pay taxes. I had fully expected to and budgeted for it. Seems sometimes one does slip by, but in my experience any package bigger then a stuffed letter you should expect to have to fill in extra paperwork and add both +21% VAT and + €12 handling

---

The hard problem seems to be only V3.0. I recall no-one (as-yet) reported self-destruct problem on a V2.9 or V3.1 firmware.
The lesser problem of Sine corruption did happen on V3.1, but they included the "fix sine" option into the PC software

I think the counts are:
5 people reported self-destructed V3.0
2 people reported sine corrupt on V3.1

---

As to the redevelopment board: I am not very active so I should probably not complain and be happy with whatever comes out...

But I would like to mention that the most obvious board to redevelop for is not some "yet another" board, but simply the panel included with the FY6600
After all, if you clear the F103, it is just as good as new, and just as much/little work to program then any other STM32 F0, F1, F7 board. All we need to do is figure out the GPIO pin to button mapping, but you would have to make such a map on a completely new board also.

So my advise/request: please do all redevelopment on a F103 with similar GPIO mapping so it fits the original.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 05, 2018, 08:45:41 am
Update on my firmware extraction: (tl;dr: not good)

I spend most of this weekend on the frauenhofer 3.3 Debug Exploit attack.
- It should works on a locked F051 (but I stupidly only ordered 1)
- It works :) on an unlocked  :-\ F103
- It does not work on an locked F103

Working on an unlocked F103 is actually not as trivial as you may think:

The attack works by reading one byte per reset cycle in a race condition with the flash lockdown. You can extract the exact same one byte in the exact same method if the flash is not locking down (you simply always win the race).  And this shows that the cabling is good and your commands work etc.
Also due to the UART debugging and porting attempt (see below) I feel I am now getting a quite good understandinf of code and attack (definitely more then from just watching the powerpoint and video).

For example, this is how I learned of yet another structural difference: Unlike the F051, on the F103 the SWD (single wire debug) shares its pin with JTAG and you need to send a special bit-train to disable JTAG first. It is not impossible this bit-train is pre-warning the debug-lockdown, thus is slowing us down enough so that we always loose the SWD race. But as mentioned in previous post, it could also be that the F1 family uses a different internal lockdown logic altogether, as witnessed by the fact it does not have a RDP-2 level.

Interesting was that the frauenhofer code already had code to switch the GPIO pin from JTAG to SWD, but it was commented out. Shows that they too had been testing somewhat seriously on the F1 family. Not sure though if they corrected the timing for a 72MHz bus rather then a 48MHz one.

The reason I ordered only one F051 is I naivety though I could run the extraction code on a blue-pill F103 with my F051 as the target.
So I learned the F0 and F1 are *really* different. Even GPIO programming is using completely different methods, and porting the code is a drag.
I will order a 2nd F051 though. But to be honest, only for the learning of it, and maybe because I want to be able to say I did actually extracted code, not just did armchair research. Bug given the huge differences between F0 and F1, I have no real belief anymore on success.

---

Additional rant: I spend half the weekend fighting the wrong enemy. Turns out I had a usb-rs232-ttl cable that "somewhat" worked, enough to make me think it worked (typing; test transfers), but working erratically when driven by the F051 non the less. And no, it was not a Xon/Xoff thing. Its now cut into a thousand pieces in the bin so I never accidentally use it again.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 05, 2018, 10:02:31 am
Ahh that would be a pitty. Damn JTAG.

Changing the sequence of commands perhaps?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on February 05, 2018, 06:47:09 pm
Hi everybody, sorry I couldn't focus mor on this project :(, just a quick note regarding the SWI/JTAG issue:

I was wondering if the SWI and JTAG clock are independent of the CPU clock, maybe we can slow down enormously the MCU clock, like 100KHz or such and use the fastest possible clock for the JTAG/SWI if they are synchrone with their own clock ?

 Cheers,
 DC1MC

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 05, 2018, 07:38:06 pm
Like your thinking. But I wouldn't think so. The PLL is doing havoc here I'm afraid. Worth a look though feeding an external clock which will be enough for the PLL to run and start the SWI interface.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 05, 2018, 08:05:33 pm
Lol, I was looking at the clock config as I was reading this....
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on February 05, 2018, 08:24:17 pm
Let the PLL wobble, as long as it spits a bite it can be as bad as possible, there is no need to run any code, I hope that the SWI interface is a simpler state machine and it will suck a byte, eventually after many tries :).

 Cheers,
 DC1MC 
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on February 05, 2018, 10:23:18 pm
Some updates: I have now written the basic functions for the FPGA (register read/write, flash erase/write/read) some macro functions (waveforms read/write and resample for display), a startup function like the original one (flash test, FPGA init, Waveform loading for the FPGA), and I am able to command the FPGA from my STM32 dev board.
I have not seen any model related limitation in the FPGA: increasing to 110Mhz the frequency of a sine wave ... outputs a 110Mhz sine wave (well, not the prettiest one  :))

As the serial protocol is documented, I have now connected my dev board to the other ribbon cable (serial link) and am working on programming the basic serial functions so that I can use the PC Software to control the FPGA through the dev board.
We should have shortly the basic tools needed to go on with the next parallel steps, which could be:

- Working on the GUI directly on the FP (which could directly use FPGA functions already tested with the serial protocol)
- Describing remaining high level functions (like sweep done by the FP...)
- Extending internal functions Library (Modulation, sweep, input, ...)
- Extending serial protocol functions
- Working on a new PC Software
- ...

Of course we will have to choose a toolchain before. At the moment I use Keil µvision with my dev board (with STM32F10x_StdPeriph_Lib_V3.5.0) but other choices could be fine as well (arduino with STM32duino for example could also be fine and easy for upgrades). We also have to see what kind of LCD is used...


But I would like to mention that the most obvious board to redevelop for is not some "yet another" board, but simply the panel included with the FY6600
After all, if you clear the F103, it is just as good as new, and just as much/little work to program then any other STM32 F0, F1, F7 board. All we need to do is figure out the GPIO pin to button mapping, but you would have to make such a map on a completely new board also.

So my advise/request: please do all redevelopment on a F103 with similar GPIO mapping so it fits the original.
Yes, and before using the FP as dev board, any STM32F103c8t6 like this one will be perfect https://fr.aliexpress.com/premium/STM32F103c8t6.html?d=y&origin=y&blanktest=0&tc=ppc&initiative_id=SB_20180205135516&isViewCP=y&catId=0 (https://fr.aliexpress.com/premium/STM32F103c8t6.html?d=y&origin=y&blanktest=0&tc=ppc&initiative_id=SB_20180205135516&isViewCP=y&catId=0)


Reply #671 gives a link to a user manual for the FY6600 but that manual is V2.2 from July, 2017 and the FeelTech home page has what appears to be the latest v2.9 from August, 2017. The date on the download link for the FY6600 English manual says 2017-10-17. 

http://en.feeltech.net/index.php?case=archive&act=list&catid=6 (http://en.feeltech.net/index.php?case=archive&act=list&catid=6)

The PC control software is now also up to v5.5 (may be worth trying the repair_sine option again?), and other documents include detailed descriptions of the PC -> Device serial communication and arbitrary waveform data transfer protocols, which might come in useful.
Yes very usefull. Even the PC software source code seems to be included.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 06, 2018, 06:59:19 am
Some updates: I have now written the basic functions for the FPGA (register read/write, flash erase/write/read) some macro functions (waveforms read/write and resample for display), a startup function like the original one (flash test, FPGA init, Waveform loading for the FPGA), and I am able to command the FPGA from my STM32 dev board.
I have not seen any model related limitation in the FPGA: increasing to 110Mhz the frequency of a sine wave ... outputs a 110Mhz sine wave (well, not the prettiest one  :))

As the serial protocol is documented, I have now connected my dev board to the other ribbon cable (serial link) and am working on programming the basic serial functions so that I can use the PC Software to control the FPGA through the dev board.
We should have shortly the basic tools needed to go on with the next parallel steps, which could be:

- Working on the GUI directly on the FP (which could directly use FPGA functions already tested with the serial protocol)
- Describing remaining high level functions (like sweep done by the FP...)
- Extending internal functions Library (Modulation, sweep, input, ...)
- Extending serial protocol functions
- Working on a new PC Software
- ...

Of course we will have to choose a toolchain before. At the moment I use Keil µvision with my dev board (with STM32F10x_StdPeriph_Lib_V3.5.0) but other choices could be fine as well (arduino with STM32duino for example could also be fine and easy for upgrades). We also have to see what kind of LCD is used...

^^^HERO^^^

A bad 110MHz sine is expected off course since the 165MHz DAC, but the limit is not there. Very nice all in all.

The display is a ILI9341 for 99% sure. The pinout is the classic 18 pin for this type op display. Link for similar display (https://www.solidrop.net/product/free-ship-5pc-lot-2-4inch-spi-tft-lcd-screen-18pin-240-320-color-lcd-drive-ic-ili9341-4io-only-for-stm32-mcu-raspberry-pi.html)

But I would like to mention that the most obvious board to redevelop for is not some "yet another" board, but simply the panel included with the FY6600
After all, if you clear the F103, it is just as good as new, and just as much/little work to program then any other STM32 F0, F1, F7 board. All we need to do is figure out the GPIO pin to button mapping, but you would have to make such a map on a completely new board also.

So my advise/request: please do all redevelopment on a F103 with similar GPIO mapping so it fits the original.
Yes, and before using the FP as dev board, any STM32F103c8t6 like this one will be perfect https://fr.aliexpress.com/premium/STM32F103c8t6.html?d=y&origin=y&blanktest=0&tc=ppc&initiative_id=SB_20180205135516&isViewCP=y&catId=0 (https://fr.aliexpress.com/premium/STM32F103c8t6.html?d=y&origin=y&blanktest=0&tc=ppc&initiative_id=SB_20180205135516&isViewCP=y&catId=0)

I'm receiving the unit from Mark today and can test all the things we need. I'm not much of a C++ hero myself but sure can monkey test the crap out of things. So if things need to be tested just send the hex file and I'll flash it once I receive my ST-Link clone this or next week.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 06, 2018, 07:31:32 am
Of course we will have to choose a toolchain before. At the moment I use Keil µvision with my dev board (with STM32F10x_StdPeriph_Lib_V3.5.0) but other choices could be fine as well (arduino with STM32duino for example could also be fine and easy for upgrades). We also have to see what kind of LCD is used..

Wow, you guys are actually pulling this off.. Very impressed

Putting this in an STM32duino toolchain is a novel but interesting suggestion. But it would mean all your code so far has to be rewritten right? Painful.
Then again, it has the advantage that people can more easily make local mods, or even do a quick temp hardcode of some sort of "special signal train" by coding very fast changes directly to the FPGA. After all, everybody and their grandmother know how to slightly mod an pre-existing Arduino program.

But it does mean the USB pins that STM32duino bootloader uses should not be used yet. Need to check that.

If it works, it would make it easier for someone else to pick up should you (heaven forbid) loose interest.
Of course, it also means there is going to be like a bazillion forks and variants on the internet.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 06, 2018, 07:44:34 am
I have not seen any model related limitation in the FPGA: increasing to 110Mhz the frequency of a sine wave ... outputs a 110Mhz sine wave (well, not the prettiest one  :))
62.5MHz should be pretty still. And 125MHz should be better then 110MHz.
Due to them being nice round numbers.

A bad 110MHz sine is expected off course since the 165MHz DAC, but the limit is not there. Very nice all in all.
The DAC is actually overclocked to 250MHz. But 4 samples per sine is really the minimum, so practically 60 (62.5) MHz would indeed be the max.


Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: scott0999 on February 06, 2018, 06:26:53 pm
 I don't see the firmware specified anywhere when ordering one. Any way to be sure I get the latest 3.2 firmware?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on February 06, 2018, 06:44:08 pm
I don't see the firmware specified anywhere when ordering one. Any way to be sure I get the latest 3.2 firmware?
Uhmm, ask the seller  :-// ? I did so, and still got 3.1, they don't give a rat behind.  :-\
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on February 06, 2018, 06:55:28 pm
Putting this in an STM32duino toolchain is a novel but interesting suggestion. But it would mean all your code so far has to be rewritten right? Painful.
Not really. I tried not to code it the way my grandmother would have done it  ;). The FPGA functions are in a library which does not access directly GPIOs, and low level functions calls (SPI) are macros defined outside the library in a config file.

Then again, it has the advantage that people can more easily make local mods, or even do a quick temp hardcode of some sort of "special signal train" by coding very fast changes directly to the FPGA. After all, everybody and their grandmother know how to slightly mod an pre-existing Arduino program.
That is exactly the point, except that we are just talking to the FPGA  not programming it.

If it works, it would make it easier for someone else to pick up should you (heaven forbid) loose interest.
Exactly my point again but it would be more a lack of time than a lost of interest.
I tried STM32duino and a STM32F103c8t6 for the replacement of  the VFD display of a fluke 8842A with a SSD1322 OLED display: no problems!.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 06, 2018, 07:04:14 pm
I know it was talked about, but did anyone already map out all the buttons and connections of the FB?
If not, I may have a go at that, but I do not want to be doing duplicate work.

Especially the use of PA11;12; PC12;13;14;15 may be important to figure out to see if STM32duino could run on this board (with a standard bootloader)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 06, 2018, 07:56:14 pm
I know it was talked about, but did anyone already map out all the buttons and connections of the FB?
If not, I may have a go at that, but I do not want to be doing duplicate work.

Especially the use of PA11;12; PC12;13;14;15 may be important to figure out to see if STM32duino could run on this board (with a standard bootloader)

I have, and I'm in the process of making the schematics in Eagle.
Buttons are in a 4x4 matrix on PB0..PB7

PA11 is LCD backlight
PA12 is Buzzer

PC12 does not exist

PC13 is LCD reset
PC14 not used
PC15 not used
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 06, 2018, 08:50:19 pm
Hmm, PC14/15 would be the 32K crystal. I guess there is none? Then in initialization we should ensure RTC (real time clock) uses a different source.
PC12/13 is often the dev board user button & led, but that is OK we can redefine those in the bootloader. (Where are the 3 leds anyway?)

PA11/12 is a pity though. They are for the Arduino USB sketch upload
If they are used as GPIO, we cannot use it to upload a sketch.

Alternative would be serial, but that uses PA9/10 and constantly change the BOOT0 jumper. So not easy and anyway PA9/10 are already hooked up elsewhere. I am surprised those are not the ones running to the serial header on the backside.

Yet another upload alternative would be STLink on PA13/14. Are those free at least? Probably they are, I bet its how they program in the factory.
Soldering in a standard STLink header would not be a bad idea anyway. And a clone STlink is cheap enough to permanently mount one inside the device


BTW: I thought of a disadvantage to STM32duino: it may be a low threshold. But it does not have a proper debug function where we can step through the code.
If we have to integrate a STLink anyway, maybe Keil is not so bad afterall. (I say 'we' but I am not actually writing code. This is all just musings for your consideration, fremen67)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 06, 2018, 09:09:57 pm
Just made the first draft, not all is in, but keys,leds and LCD (pdf).

Leds are for power and CH1,CH2 on/off

The ST-Link is on JK1 so that is the one to use in my opinion. Standard four pin ST-Link (image).

Serial to the back are on PA2 and PA3

I like the idea of using the Atollic TrueSTUDIO mentioned earlier in this topic, worth checking/trying out, its free as of the new version.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on February 06, 2018, 10:23:26 pm
Solid work guys, well done ,

Did the supplier specify which firmware you were getting DCMC? I asked the same question about my unit and got no response from the seller. Im thinking on account of weight I might not have to pay the import duties ,usually dont take a hit if its delivered via regular post either ,often sellers missquote the value as well .I ordered a new multimeter as well ,that is due tomorrow by courier ,I might not be so lucky on that parcel .

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on February 07, 2018, 12:14:31 am
Yet another upload alternative would be STLink on PA13/14. Are those free at least? Probably they are, I bet its how they program in the factory.
Soldering in a standard STLink header would not be a bad idea anyway. And a clone STlink is cheap enough to permanently mount one inside the device
I did not use the arduino bootloader last time as the flash memory is already pretty small. I just used the STlink for download. That's a cheap and convenient solution.

BTW: I thought of a disadvantage to STM32duino: it may be a low threshold. But it does not have a proper debug function where we can step through the code.
If we have to integrate a STLink anyway, maybe Keil is not so bad afterall. (I say 'we' but I am not actually writing code. This is all just musings for your consideration, fremen67)
That's right but not really a big deal. I am more concern about the code size limitation of the free version of Keil for future developments.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on February 07, 2018, 12:29:12 am
Just made the first draft, not all is in, but keys,leds and LCD (pdf).

Leds are for power and CH1,CH2 on/off

The ST-Link is on JK1 so that is the one to use in my opinion. Standard four pin ST-Link (image).

Serial to the back are on PA2 and PA3
Well done :-+ Very promising!

I like the idea of using the Atollic TrueSTUDIO mentioned earlier in this topic, worth checking/trying out, its free as of the new version.
I never used it but I will try. My project should already be compatible with it.

Note: The PC Software already wants to talk to me. I just said to him I was "FY6600-60M"  when he asked ;)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Malvineous on February 07, 2018, 02:07:11 am
Is there a place yet where this stuff is documented?  The thread is becoming a bit long to read through to find info on the protocols etc.

If not, might I suggest someone create a GitHub repository and enable the wiki for the repo?  Then we can add interested people to the project and they will be able to document the latest info in a nice clean wiki structure for all to see.  Happy to be the one to set this up if it would help.  (GitHub account required, git skills not required, editing the wiki is web based like any other wiki.)

The reason I ask is that I'm wondering whether the serial protocol between the FP and FPGA has any unused commands, e.g. that allow the FPGA to read or write memory on the FP board.  If it did, it might be another way to dump the firmware, by sending the FP commands to read out the contents of the ROM, which won't be locked if it's the program itself performing the reads.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on February 07, 2018, 05:20:53 am
Sounds like a good plan Mal ,
The Github seems to be the place for it alright ,its nice to see the internet or at least one small part of it working in true spirit of sharing and open source.

Im sure some of the other contributors will be able to look into your suggestion for getting the firmware out from behind bars .
From Fremens work we have seen the high frequency limit is down to restrictions in how the front panel commands the FPGA ,so at least via the programer and some software looks like the Feeltech spoiler can be circumvented and we can all have a 60mhz AWG for the price of a 16mhz unit and the appropriate programming  tools.

You know what the funny thing about all this is , our efforts here could actually end up with Feeltech selling even more of these units ,everybody can have their cake and eat it ,win win for all .

Has anyone with a defective unit got any proper response from the factory yet ? It seems totally short sighted of the 'Feelers' just to leave you guys swinging in the wind ,when for a small cost the few who had failed units could be sorted and that in itself would make more people think about buying the product, they have to learn to play the long game to build any kind of brand loyalty .
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 07, 2018, 06:51:39 am
Had a go with my account for reading only up until now.

https://github.com/DerKammi/FY6600-15-30-50-60M (https://github.com/DerKammi/FY6600-15-30-50-60M)


Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: skander36 on February 07, 2018, 12:15:54 pm
I don't see the firmware specified anywhere when ordering one. Any way to be sure I get the latest 3.2 firmware?
Mine has arrived Monday and has 3.2 . It was ordered on 24 Jan.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on February 07, 2018, 01:34:19 pm
Wow Skander ,
That was quick ,I ordered on the 15th Jan but still no sign and I have a trail of other packages ordered mid December about half a dozen of which  still havent landed .

I was reading up a few other articles on busting open  Stm32's ,maybe another angle worth looking at might be the update for the sine
wave issue ,there must be a facility to re-write some portion of the code on the device for this to work ,so maybe its another attack vector worth considering .

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: skander36 on February 07, 2018, 01:45:44 pm
Wow Skander ,
That was quick ,I ordered on the 15th Jan but still no sign and I have a trail of other packages ordered mid December about half a dozen of which  still havent landed .

I was reading up a few other articles on busting open  Stm32's ,maybe another angle worth looking at might be the update for the sine
wave issue ,there must be a facility to re-write some portion of the code on the device for this to work ,so maybe its another attack vector worth considering .
I ordered from Banggood and I have paid 1,43 E for option "European Direct Mail" .
Total Price for 60MHz version was 92.13E . Through Dutch Mail , no customs tax .
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on February 07, 2018, 02:21:54 pm
Wow Skander ,
That was quick ,I ordered on the 15th Jan but still no sign and I have a trail of other packages ordered mid December about half a dozen of which  still havent landed .

I was reading up a few other articles on busting open  Stm32's ,maybe another angle worth looking at might be the update for the sine
wave issue ,there must be a facility to re-write some portion of the code on the device for this to work ,so maybe its another attack vector worth considering .

Some quick clarifications: the FP is master to the FPGA signal board, so there is no way for the SB to tell anything special to the FP. Also all the waveforms are stored in the external flash on the SB.
Busting open the STM32 has been tried for this version, you should look 1-2 pages back, due to the fact that the JTAG interface shares the pins with the SWI interface we're using too much time switching the interfaces and lose the race, there is still a chance to replace the STM32 quarz with external very slow clock source, but the prognosis is not so good.
So far, if there is no hidden external command over the serial line to overwrite the STM32 firmware than the only solution is to write a new one.

  So far, let's hope that our efforts for a new firmware will give results and official fw 3.2 is not too miserable.

  Cheers,
  DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: pauluzs on February 07, 2018, 03:37:41 pm
Just got one from Frankfurt today, FW 3.2

After reading this tread i was curious to see what could be done.
Before doing any of the psu and clock hardware mods, it would be nice to be able to use this device with Sigrok and maybe something like gnuradio on linux.

After playing around with serial the commands as listed in "FY6600 Serial communication protocol" and having a quick glance at the pcb. It seems the ch340 and the tx/rx headers on the back are both connected to the FP. In other words i could not use the serial command with the FP disconnected.

This would be in line with the findings done by cybermaus, fremen67, DC1MC and others. Based on this we would now send all the know serial commands and capture the corresponding spi command from the FP to Winboud?
Would like to know how this communication works, (SERIAL>)FP>WINBOUND and FPGA polls winbound for changes? or does the FP Sends some kind of notification/interrupt to FPGA?

This way it would be possible to replace the FP with something else like a dev board(already done), microcontroller or do a SPI man in the middle between FP and FPGA with something like a rpi that has 2 spi ports.

Last one, if it  could be done. what would it take to have a external clock reference on one of the BNC connectors or header pins instead of modding the pcb clock circuit?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: scott0999 on February 07, 2018, 03:40:00 pm
I don't see the firmware specified anywhere when ordering one. Any way to be sure I get the latest 3.2 firmware?
Mine has arrived Monday and has 3.2 . It was ordered on 24 Jan.

sweet where did you order from?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: skander36 on February 07, 2018, 03:59:18 pm
Romania.
Two posts above .
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 07, 2018, 06:33:28 pm
Ok, I think I am ready to close the firmware readout topic.
My 2nd STM32F051 board arrived, and as expected, I can simply reproduce the frauenhofer result, and readout a RDP-1 protected board.
(see images)

It also means my setup is correct, and so the same method cannot be used on a F1 board.
Not unexpected, but at least I now also actually hacked a F051 board, so give my failed F103 attempts some credibility.

tl;dr; some more insight why F0 != F1


Busting open the STM32 has been tried for this version, you should look 1-2 pages back, due to the fact that the JTAG interface shares the pins with the SWI interface we're using too much time switching the interfaces and lose the race, ......

Well, to go into detail: That is not *the* reason, it is merely *one* of the many possible reasons. It could really be any of these:

- F0 vs F1 have different protection implementation, F0 has 2 levels, F1 has 1 level  - (die difference)
- F0 vs F1 have different debug implementations. F0 has only SWD, F1 has JTAG and SWD - (die difference)
- F0 vs F1 have different debug implementations. F0 has only SWD, F1 has JTAG and SWD - (switching to SWD may already trigger the lockdown)
- F0 vs F1 have different core bus matrix design. F0 with M0 core reads flash over shared bus. F1 with M3 code has dedicated ICODE bus (hack is based on bus conflict race)

All 4 of the items above mean that there is a key difference on the section specifically relevant to this attack, so a relevant part of the chip die was redesigned between the two chip families, and so any bug could or could not be there.

So, does that mean the F1 is uncrackable? I do not know. But it does mean that it was rather naive of me to think/hope the F0 debug attack would simply map to the F1.
We may think the chips are similar because we use them similar. But they are really different though and through.

If F1 is hackable, it would need all new top-level base reseach


There is still a chance to replace the STM32 quarz with external very slow clock source, but the prognosis is not so good.
So far, if there is no hidden external command over the serial line to overwrite the STM32 firmware than the only solution is to write a new one.

Alas no. I lol'ed because when this was mentioned, I literally was looking at the clock diagram on my other monitor.
But (apart from the arguments above) the flash controller has its own fixed build in RC clock. To win the race (if one exists on the F1) we would have to make the flash controller slower, and the debug access (APB bus and AHB bus) faster.

And that is the opposite of what we can do. Officially, we can make APB/AHB slower. I guess we could try overclocking. But we do not even know if there is a race condition at all, the F1 is just too different. So I repeat, it would need all new research from the bare basics, not buiding on top of Frauenhofer. Where do we stop, I was not planning on promoting on this.

So, not to be negative, but I am calling it quits.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 07, 2018, 06:48:20 pm
BTW: I have two barely used STM32F051 Discovery boards for sale, if anyone is interested    ;D
Unlocked with factory default blink program loaded.   :P
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 07, 2018, 07:34:43 pm
Ahh that is a pitty Cybermaus. Great goings never the less. A lot more has to be discovered then. Would you share the code you used?

I'm resuming the schematic entry now :)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 07, 2018, 09:14:45 pm
Frontpanel schematic are done :) Offcourse some faults can be there and the PA0 signal going to the FPGA is unknown to me as of yet.

The transistors for driving the buzzer and backlight are probably MOSFETs, but I found these first :)

On to the main PCB :D
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on February 07, 2018, 09:35:28 pm
Oh well Cybermaus ,
thats a pity but a great effort you made all the same . Even though you didnt reach the finish line I guess its all part of the fun and some lessons were learned at least .
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on February 08, 2018, 12:36:08 am
Frontpanel schematic are done :) Offcourse some faults can be there and the PA0 signal going to the FPGA is unknown to me as of yet.

The transistors for driving the buzzer and backlight are probably MOSFETs, but I found these first :)

On to the main PCB :D
:-+
The model I have on my FP is STM32F103c8t6. You have a STM32F103cbt6?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 08, 2018, 06:16:57 am
That is correct, this is what is in the library, Lazy mode.

Only difference is flash size, the c8 has 64k instead of the 128k in de cb. Pinout is the same.

fremen67: Do you have any documentation for the FPGA comms. to share for on the Git? Or some code even? Don't mind if it is tidy or not. Just want to have a look.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 08, 2018, 06:47:22 am
As mentioned, the only difference between the C8T6 and CBT6 is 64KB vs 128KB flash
But in fact, most C8T6 (blue-pill) users (almost all)  (http://wiki.stm32duino.com/index.php?title=Blue_Pill#128_KB_flash_on_C8_version)report it has 128KB anyway..

Probably a way to sell failed CBT6 chips, and not having enough production fail.
Quite possible Feeltech is buying the cheaper one, but using all 128KB anyway.

Just for fun, I check all my C8T6: both unlocked ones have 128KB usable
The one in my Feeltech I think too, but it reports "inaccurate probe":

Code: [Select]
Open On-Chip Debugger
> reset halt
target state: halted
target halted due to debug-request, current mode: Thread
xPSR: 0x01000000 pc: 0x08000144 msp: 0x20004bb8
> flash banks
#0 : stm32f1x.flash (stm32f1x) at 0x08000000, size 0x00000000, buswidth 0, chipwidth 0
> flash probe 0
device id = 0x20036410
STM32 flash size failed, probe inaccurate - assuming 128k flash
flash size = 128kbytes
flash 'stm32f1x' found at 0x08000000
>

I think it means the chip reports 128K, but he cannot validate it by reading the 2nd half.
They do all 3 give the same device id of 0x20036410
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 08, 2018, 10:40:57 am
Do I read it correctly in a way that 64k is fully guaranteed to work and 128k is not 100% validated?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 08, 2018, 11:35:14 am
Yes, if you follow the link (http://stm32duino.com/viewtopic.php?t=1323&start=20#p18962), you find at 2 users Sylvan_YZY and pokemon99 reported a C8T6 with the nominal 64KB. But both of them also had the chip only report 64K, so if the chip reports 128K, you can assume it is usable. Assume, but I guess no warranty from ST :)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on February 08, 2018, 11:08:14 pm
That is correct, this is what is in the library, Lazy mode.
Only difference is flash size, the c8 has 64k instead of the 128k in de cb. Pinout is the same.
As mentioned, the only difference between the C8T6 and CBT6 is 64KB vs 128KB flash
But in fact, most C8T6 (blue-pill) users (almost all)  (http://wiki.stm32duino.com/index.php?title=Blue_Pill#128_KB_flash_on_C8_version)report it has 128KB anyway..
Yes I also have a mix of C8T6 and CBT6 boards. Not a big deal when you are insured to have the minimum specs.
For us it does matter in the way that we should target 64k as the maximum program size and not 128k.
I guess this is not a problem with real code size as there won't be a lot of code in our case but this could be more important for bitmaps and fonts storage. The UI usually needs some room for cool stuff (well... some UIs do, some others don't ;))
fremen67: Do you have any documentation for the FPGA comms. to share for on the Git? Or some code even? Don't mind if it is tidy or not. Just want to have a look.
Sure. All my "working" notes are in an excel file. The summary sheet is the pdf file I posted some days ago. Maybe not the best format to put on a github... but I suppose for the moment beeing you can post the pdf file as is...
For the code you can post the FPGA Library (FPGA.c) plus a module I used for testing puposes (Tests.c surprisingly  :)) This might help understand the FPGA library which should already be understandable by itself. At least I hope :P
The next module I will post will be the serial protocol which will be less interesting as already documented by Feeltech. Maybe you could also post the original document from Feeltech ...
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on February 09, 2018, 12:11:29 am
I just came across this:

https://www.aliexpress.com/item/High-Precision-Digital-Dual-channel-DDS-Function-Signal-Generator-Arbitrary-Waveform-Pulse-Signal-Generator-1Hz-100MHz/32835207150.html (https://www.aliexpress.com/item/High-Precision-Digital-Dual-channel-DDS-Function-Signal-Generator-Arbitrary-Waveform-Pulse-Signal-Generator-1Hz-100MHz/32835207150.html)

I very well think I might get one at $75.   It uses a resistor ladder instead of an IC for the DAC.   I ran across a 5 V linear supply I built long ago which should do just fine powering the METERK JDS6600.  I might enjoy having a unit that didn't require work to be able to use it properly.  But one is paying about $35 for the 4 BNCs on the back of the FeelTech.  Plus the aggravation factor.  I wonder how many other names it sells under on AliExpress.

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: bitseeker on February 09, 2018, 12:18:41 am
I think I've seen the JDS-looking version being sold under several names. I don't know if they're rebadged or just look-alike.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Candid on February 09, 2018, 12:53:59 am
I just came across this:

https://www.aliexpress.com/item/High-Precision-Digital-Dual-channel-DDS-Function-Signal-Generator-Arbitrary-Waveform-Pulse-Signal-Generator-1Hz-100MHz/32835207150.html (https://www.aliexpress.com/item/High-Precision-Digital-Dual-channel-DDS-Function-Signal-Generator-Arbitrary-Waveform-Pulse-Signal-Generator-1Hz-100MHz/32835207150.html)
This is the 30MHz version. You may search for "rd jds6600" on Aliexpress and you will find the 5 models 15, 30, 40, 50 and 60MHz of this JDS6600 series products. The psu is 5V/2A. It needs at least stable 5V/1200mA to start and run properly. I have this rd JDS6600 and the FeelTech FY6600.

From the technical side as a signal generator the FeelTech is better. You may compare the technical data. But with an external linear 5V psu you can easily omit the known high voltage to earth problem with the JDS6600. The mechanical user interface is way better than that of the FeelTech.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on February 09, 2018, 01:06:39 am
One of the JDS sellers claims that the engineer who designed the series, and another engineer involved in later work, work for them. And that the JDS is the most recent version.

So it would appear that a designer has created a design, sold it to a manufacturer, then sold sold lower cost designs to other companies. It may well be something like:

Bored engineer in LCD factory designs FPGA/MCU AWG in spare time.  Convinces management to market it.  But management gets weird and puts a super cheap front panel on the units because the 4 BNCs out the back cost so much. So engineer gets ticked off quits and gets job designing similar product.  He goes the opposite end of the feature spectrum, gets a decent front panel and eliminates the back BNCs and we have the JDS6600.  FeelTech and FD make and sell instruments to order with whatever features you are willing to pay for added.

How true I don't know, but it seems like a reasonable fit to the facts.  FeelTech as jerks is quite obvious.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Candid on February 09, 2018, 01:39:00 am
Something like this. The user interface of the two products is nearly identical so the engineers behind these products may come from one company or is identical. The JD6600 has the DC2DC converters on the mainboard. It's a pitty that they use a smpsu and not a linear one. Could be so easy.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 09, 2018, 07:23:01 am
But with an external linear 5V psu you can easily omit the known high voltage to earth problem with the JDS6600.
Not sure if that is true. An external switched PSU has the same problem as an internal one. The only thing is you can more easily switch out a cheap one for a better one, but they both will have leakage through the mandatory capacitor.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 09, 2018, 09:00:20 am
Filled the Git with various info on Hardware/Software/Mods and photos.

https://github.com/DerKammi/FY6600-15-30-50-60M

Lot less scrolling in the pages. Please let me know if something is missing if you want it in.

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: pauluzs on February 09, 2018, 09:50:34 am
Hi DerKammi,

Couldn't find a overview of the serial commands on the git.
See attached speadsheet
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 09, 2018, 10:00:07 am
Done
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on February 09, 2018, 12:02:39 pm
Hi DerKammi,

Couldn't find a overview of the serial commands on the git.
See attached speadsheet
Hi pauluzs,
Thank you for helping.
The "SPI Register" column in your document should be removed as it suggests  that there is one register associated to each command.
The serial protocol is only handled by the Front Panel CPU and is transparent for the FPGA.

@DerKamni
The full serial protocol description relased by Feeltech could also be added as well to the repository.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 09, 2018, 12:21:05 pm
Added
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 09, 2018, 01:00:41 pm
Parts identified: I though we had in the mean time discovered the opamp was not a "unknown THS30021" but instead a known type THS3002I
May still be a fake, but at least a known number:

http://pdf1.alldatasheet.com/datasheet-pdf/view/28726/TI/THS3002ID.html (http://pdf1.alldatasheet.com/datasheet-pdf/view/28726/TI/THS3002ID.html)

Also note the PCB layout is such they can use either 2 THS3001, or 1 THS3002

Edit: that was in the FeelTech FY3224 thread (https://www.eevblog.com/forum/testgear/feeltech-fy3224s-24mhz-2-channel-dds-aw-function-signal-generator/msg879289/#msg879289) that I picked that up.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 09, 2018, 01:10:04 pm
You're right, made a typo in this. Updated the txt file.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on February 09, 2018, 11:41:43 pm
Hi DerKammi ,
Looks like your Github post comes up top of the list when I search 'FY6600' now  .
With a bit of luck it should draw in a few more people interested in our cause and with it maybe some extra inspiration and technical wizardry too .
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Candid on February 10, 2018, 12:19:21 am
But with an external linear 5V psu you can easily omit the known high voltage to earth problem with the JDS6600.
Not sure if that is true. An external switched PSU has the same problem as an internal one. The only thing is you can more easily switch out a cheap one for a better one, but they both will have leakage through the mandatory capacitor.
That is why I wrote an external LINEAR psu. I replaced the external smpsu with a linear one and everything is fine.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 10, 2018, 05:35:57 am
Ah, sorry yes, I missed the linear part.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 10, 2018, 06:45:29 am
Hi DerKammi ,
Looks like your Github post comes up top of the list when I search 'FY6600' now  .
With a bit of luck it should draw in a few more people interested in our cause and with it maybe some extra inspiration and technical wizardry too .

So it does, that is quick. Would be great if we could create that momentum.

Despite the small "bugs" the device has it is worth the price to make some killer custom open source firmware.

I only that FPGA could be... ahh well dreams are for the keeping.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 10, 2018, 03:02:42 pm
Sure. All my "working" notes are in an excel file. The summary sheet is the pdf file I posted some days ago. Maybe not the best format to put on a github... but I suppose for the moment beeing you can post the pdf file as is...
For the code you can post the FPGA Library (FPGA.c) plus a module I used for testing puposes (Tests.c surprisingly  :)) This might help understand the FPGA library which should already be understandable by itself. At least I hope :P
The next module I will post will be the serial protocol which will be less interesting as already documented by Feeltech. Maybe you could also post the original document from Feeltech ...

Can I have the .h files as well? want to have a go with my fresh blue pill boards on Mark his generator this evening.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Lanvernazal on February 11, 2018, 04:20:20 am
I have made and change a linear PSU for my FeelTech FY6600 .
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 11, 2018, 06:14:13 am
Well somebody had a busy weekend :)

Nicely done in the limited space.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on February 11, 2018, 09:05:32 am
I have made and change a linear PSU for my FeelTech FY6600 .

Nice job Lanvernazal, you did it well.
On my side, because I am a lazy man, my choice was to make some mods on the stock one.
Upgrading some capacitors, switching diodes, earthing the FY6600 with an appropriate socket for the mains input.
Et voila !!



Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on February 11, 2018, 09:15:10 am
For the German residents, a cheap one (no connection with the seller):

Quote
Biete   Meßgeräte
(Anzeigen-Nr.: 514605)    2-Kanal DDS Signalgenerator Feeltech FY6600-60
Ich biete einen unbenutzten Signalgenerator vom Typ FY6600 an. Es handelt sich um die 60MHz-Ausführung. Informationen dazu finden sich reichlich im Internet. Das Gerät wurde nur einmal zum Funktionstest eingeschaltet. Es arbeitet mit der Firmware V3.2. Preis 70 Euro inkl. Versand innerhalb von DL.
 9.2.18 - 11:06 Uhr    Karsten Hansky - DL3HRT
 dl3hrt@aatis.de

 Cheers,
 DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: plb on February 11, 2018, 11:21:43 am
Has anyone who has gone to a linear PSU done any measurements that demonstrate improvements to stability, distortion, jitter, amplitude vs frequency or any other characteristics? I am mulling the possibility but haven't seen enough justification yet. My limit has been grounding the SMPS common to stop it biting.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DaveR on February 11, 2018, 11:36:42 am
I'm waiting for a 15v / 9v R-core transformer to be delivered, then I'll be doing mine - more out of curiosity than anything else, as I'm not convinced it will make much difference - then I'll give you my thoughts.  I'll be happy if it reduces the jitter somewhat.

Dave
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: plb on February 11, 2018, 09:21:59 pm
Thanks Dave, that should be a useful addition to the knowledge bank.
Will you be doing identical before and after tests?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on February 12, 2018, 06:20:31 am
Has anyone who has gone to a linear PSU done any measurements that demonstrate improvements to stability, distortion, jitter, amplitude vs frequency or any other characteristics? I am mulling the possibility but haven't seen enough justification yet. My limit has been grounding the SMPS common to stop it biting.

Well, aside the mains leakage protection a linear and good stabilized power supply will do jack against jitter (digital issue), frequency stability (oscillator) and amplitude vs frequency.
It will do a lot of good on: distortion factor of high signal levels under load, noise factor and make the amplitude more predictable. I mean if you connect a 1Mohm scope probe, you won't see too much of a difference, if you connect a 50ohm spectrum analyzer input and play a bit with the levels you'll see the difference immediately, also one can connect a scope with a 50 input and put the triangular waveform.

Someone here did the measurement and the output voltage of the power supply swings in between 12 to 17V !! volts, in different load and frequency conditions, this can't be healthy for the analogue block.

 Cheers,
 DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: CharlieEcho on February 12, 2018, 01:50:54 pm
I don't see the firmware specified anywhere when ordering one. Any way to be sure I get the latest 3.2 firmware?

Order the Kuman-branded version on Amazon (ASIN: B074TCVPVG). It's coming directly from them ("kumanshop") and as of mid-January their stock had v3.2. Boot screen identifies it as a FY6600. They're a Prime seller, so if it disappoints just send it back. Probably pricier than eBay though.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: TopLoser on February 12, 2018, 07:13:24 pm
I ordered one from eBay about 10 days ago and it came with 3.2.1 firmware
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on February 12, 2018, 07:15:46 pm
3.2.1 ?!?!

A new revision ?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: TopLoser on February 12, 2018, 07:26:55 pm
Looks like 3.2.1 to me...
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on February 12, 2018, 07:29:11 pm
Hmmm, what they did corrected this time, maybe this endless stupid repetitions of all parameters re-programming when you just change one.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on February 12, 2018, 07:48:17 pm
Sending  all parameters on any change is a good idea.  It makes the FPGA code much simpler.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on February 12, 2018, 07:49:20 pm
Sending  all parameters on any change is a good idea.  It makes the FPGA code much simpler.

FOUR times ?!?!?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on February 12, 2018, 09:26:45 pm
I was looking at the front panel pic up close and personal and thinking ,damn that looks crummy ,but then I realised the outer protective plastic wasnt  peeled off yet . I'm half thinking a layer of something like 3M weatherproof clear tape over the buttons might be a good trick for longevity , Ive seen how those polycarbonate bubble switch membranes go after years and years and its not pretty. Course that could all be in vain if the thing ends up brain dead after two weeks . still no sign of my machine yet.......
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: scott0999 on February 13, 2018, 03:10:05 pm
I ordered one from eBay about 10 days ago and it came with 3.2.1 firmware

which seller on ebay?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: TopLoser on February 14, 2018, 04:53:04 pm
Creativeonline100
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on February 14, 2018, 09:08:36 pm
Some updates on what’s going on.

1-The FPGA Module is finished for now.
2-The main Feeltech serial protocol functions are working :
- Waveform selection
- Frequence
- Amplitude
- Offset
- Phase
- Duty
- CH1/CH2 ON/OFF
- ARBs transfer
The others are foreseen but they will be added later on if/when needed.

3-I am now working on the main control module, including the Relays switching logic and output ranges limitations (Amp and Offset).
As soon as the basic functions are working (end of next week?), I will publish binaries for blue pills board. We will then be able to bypass the front panel and control the FG from the Feeltech PC Software interface. This interface would need some serious QA control but at least it already exists, every one can get it plus the source code is available).
This will allow everyone to test the new firmware without modifying the Front Panel. If it works well, I will then publish the first code source release. The cost of a blue pill board is very low, one just needs to get an ST-Link V2 to flash it (also very affordable).
I received today my second FY6600 (15MHz Model) so this will be my next dev board. Not sure for now if I will flash the FP directly or swap before the CPU with a CPU from one of my blue pills boards to have a spare…

4-Some other points in disorder :
- Reg 0x38 and 0x39 are used for rising/falling time of the square waveform (duty button)
- Need to study Square, CMOS, Adj-Pulse and DC which are handled differently than ARBs
- Sweep functions are handled partially by the FP which sends frequency setpoints in real time
- The blue pill source project should be able to compile with the free version of Keil µvision (8ko of program code/ 18ko of data now for my dev board which already includes some LCD library functions)
- Attached the software architecture I foresee for the moment
- I will open a new thread for the open source FP software as  it might polute this already long thread
- I will have one week off in 2 weeks, this might speed up things ;-)

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on February 14, 2018, 09:10:08 pm
@TopLoser: Would you be able to dump the flash memory? :)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on February 14, 2018, 11:43:57 pm
Tremendous work Fremen,
I think our project would have fallen on its ass without your expertise.
Maybe to get something back for your efforts you could consider offering pre programmed Stm32's .
Ill probably give the blue pill thing a go myself for the learning of it ,
Thanks again,
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 15, 2018, 07:00:22 am
Fremen, what is great progress you made. Highly appreciated at the work you are doing. Thanks.

I would love to help you in the coding, but compared to you're speed and knowledge I'm not much of a help I'm afraid.

Since I also have a second unit but waiting on my ST-Link I would like to try out the code you made when possible.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 15, 2018, 06:14:19 pm
Great progress. Very promising.

While not at all urgent, please remember that one of the features of the FY6600 is the ports on the backside. So you may want to keep that in mind when designing the data-structures and things that you 'foresee' for the future.

I do not think anyone mentioned them in a while, or mapped out their SPI protocols.


Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on February 15, 2018, 07:48:38 pm
The ports and the modulation stuff is interesting, starting this Sunday I can start contributing again, the Saturday is reserved for the signal generators run, but in the meantime @fremen67, if you have some capture for square wave settings or other interesting signals, please post them here, I'll love to get some eyes on them.

 Cheers,
 DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: TopLoser on February 15, 2018, 07:54:04 pm
@TopLoser: Would you be able to dump the flash memory? :)

Sorry, I’ve already shipped it out to somebody. I just handled the buying and shipping for them, complicated story don’t ask!
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on February 16, 2018, 12:20:21 am
Maybe to get something back for your efforts you could consider offering pre programmed Stm32's .
Thank you, that's kind of you but it has to remain free. A matter of principle  :)
Since I also have a second unit but waiting on my ST-Link I would like to try out the code you made when possible.
No problem. I will send you homework  ;)
While not at all urgent, please remember that one of the features of the FY6600 is the ports on the backside. So you may want to keep that in mind when designing the data-structures and things that you 'foresee' for the future.

I do not think anyone mentioned them in a while, or mapped out their SPI protocols.
Those functions are handeld directly by the FPGA as far as I know. I already documented all the related commands in my first pdf more than2 weeks ago  :P
@fremen67, if you have some capture for square wave settings or other interesting signals, please post them here, I'll love to get some eyes on them.
OK I will see what signal could be interresting to check.
Square / CMOS / Adj-Pulse and DC are now clear. They are defined with Reg 0x05 (see updated pdf)


@all of you: Thank you for your support and your kind words :)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on February 16, 2018, 05:37:07 am
@fremen67: I have a small question, do we really need to change the parameters fully to change just one, or for example the frequency can be changed by just one register operation or register operation + reload registers trigger, so just 2 register write, I'm curious haw fast one can sweep the frequency/phase ?

Also, one more thanks for your excellent work  :clap:

 Cheers,
 DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Insatman on February 16, 2018, 06:25:06 am
For anyone having problems installing the FY6600 software and getting an error "Component ‘richtx32.ocx ‘ or one of its dependencies not correctly registered or a file is missing or invalid" here is the solution.
https://www.k6jm.com/hs-setupocx.htm. (https://www.k6jm.com/hs-setupocx.htm.)   
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 16, 2018, 06:40:41 am
ehhh, just a bit quick on the feature request possibly, but a request.

I saw in the reviews that when doing a sweep we have to use the VCO to generate a signal for having a sweep output and trigger slope. Can we make it so that we use CH2 as the trigger ramp while CH1 does the sweep. Then we don't need to have the back connections attached for a simple sweep.

Since I also have a second unit but waiting on my ST-Link I would like to try out the code you made when possible.
No problem. I will send you homework  ;)

The better kind of homework in ages :)

Not sure how much room there is to spare on the free version of Keil, but I've been playing with my previous suggestion of Atollic TRUEstudio and this is actually a full grown tool with a huge amount of possibilities for free with no limit in code size. I'm not pushing anything what so ever but together with CubeMX you have a code wizard for the HAL which can init the DMA for the 2 SPI busses with a couple of clicks. I'm very impressed with it so far.

@all of you: Thank you for your support and your kind words :)

You're working hard enough, can't be thanked enough for in this topic.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Insatman on February 16, 2018, 06:55:32 am
Has anyone done a mod to improve the frequency stability?   My new unit FY6600 v3.2 has frequency jitter of about 5Hz at 10MHz.  My older JDS6600 is around 1/10 of that at 0.5Hz
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 16, 2018, 07:03:25 am
Has anyone done a mod to improve the frequency stability?   My new unit FY6600 v3.2 has frequency jitter of about 5Hz at 10MHz.  My older JDS6600 is around 1/10 of that at 0.5Hz

Check these posts:
https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1346454/#msg1346454 (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1346454/#msg1346454)

https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1389870/#msg1389870 (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1389870/#msg1389870)

I'm switching my osc for the Farnell 1611840   ASV-50.000MHZ-EJ-T -  Oscillator, 50 MHz, 20 ppm, SMD, 7mm x 5mm, 3.3 V, ASV Series. Not in need of that low jitter specs at this moment.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 16, 2018, 10:52:40 pm
Slow goings on the schematics of the main PCB. Lot of parts needing drawing which takes up quite some time. But the start is there.

Got the FPGA part from Farnell, not sure about the pinning sorted by banks in the way they did. May need to rearrange that for a more clean schematic.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on February 17, 2018, 04:14:54 am
Slow goings on the schematics of the main PCB. Lot of parts needing drawing which takes up quite some time. But the start is there.

Got the FPGA part from Farnell, not sure about the pinning sorted by banks in the way they did. May need to rearrange that for a more clean schematic.

Nice work @Der Kammi  :clap:, my signal board has some very strange rework done with some blobs of solder in between the oscillator pins on top side  :scared:, I can't wait to see what is there actually.
In the end, the FY6600 may become the best FPGA development board for mixed signal development in its price range  >:D, so we have this for us  :-+

I'm traveling to Düsseldorf in 2h to get the Anritsu boat-anchor, but starting from next week I'll recontribute again (on Sunday I'll do the autopsy ;).

 Cheers,
 DC1MC

 Cheers,
 DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on February 17, 2018, 08:59:55 am
Slow goings on the schematics of the main PCB. Lot of parts needing drawing which takes up quite some time. But the start is there.

Nice first step on drawing down the schematic of the main board, it will be very usefull for all of us.
How can I help ?
I don't have much time to spent on that, however I think I could do something to help.
What sort of EDA are you using ? EasyEDA, Tinycad..

sheers
Eric
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 17, 2018, 01:19:34 pm
@Ebel, the relais routing is a bit strange to me as the common contact looks weird up until now. If you can draw that out that would help me. A photo from a paper drawing is fine.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Insatman on February 18, 2018, 02:28:27 am
Slow goings on the schematics of the main PCB. Lot of parts needing drawing which takes up quite some time. But the start is there.

Got the FPGA part from Farnell, not sure about the pinning sorted by banks in the way they did. May need to rearrange that for a more clean schematic.

Has anyone drawn the power supply board schematic?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on February 18, 2018, 09:19:33 am
Here it is.
I don't have double checked all the components values.

This schematic shows the upgraded version I made by myself (the new values are in red).
The stock values are also mentioned.


(edited)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 18, 2018, 03:57:41 pm
Nice one Eric. No surprises in the PS division so to see. It couldn't be more skimpy on the regulation side :(
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 18, 2018, 06:11:58 pm
Soo... Those 220uF 25V, are they what you feel they should have been, or do you actually have 25V instead of the underspec'ed 16V me and others were complaining about?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on February 18, 2018, 09:14:32 pm
You're right Cybermaus my post was not 100% clear, so I edited it.
The schematic correspond to the upgraded version I made some weeks ago.
I uploaded a new one  :D
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DaveR on February 18, 2018, 09:49:59 pm
Talking of power supplies, I got my transformer on Wednesday, so I've replaced the original in mine with a linear as per the photos attached.  I set the outputs to 5.1v and +/- 12.2v, and the only component which generates any heat is the LM317 on the 5v board, which tops out at 75degC (but well within its design spec).  The transformer runs very cool, and the regulators on  the 12v board hardly get warm.  I didn't bother with a fan because a 90 minute soak test with a temperature probe inside the case showed that the internal temperature only rose to a steady 34C after an hour (10C above ambient), which I don't forsee being a problem.  Some slots in the case above the 5v board will probably lose half of the extra heat anyway, if I need to do anything at all. 

As you can see, I've also replaced the plastic disc on the encoder shaft with a "proper" knob, and this simple change has made a vast improvement in the operation and feel of the thing - I'd recommend this as a "must do" mod (I just had to move the encoder mounting board forward a couple of mm to get the shaft to protrude enough to get it into the collett of the knob).

I haven't carried out any comparative tests between the new and old PS boards yet, but I did notice as soon as I first switched it on that the oscilloscope traces appeared to be much cleaner than before, obviously due to the reduced noise level compared with the SMPS.  Everything is fine so far, after three days and several hours of operation.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Diabolo on February 19, 2018, 05:36:04 am
Hello,

@Ebel0410.
Thanks for the schema a power supply.
The symbol for 1n5819 and YG911S2 is not correct, it indicates a zener diode but it is a rectifying diode.

Regards,
Diabolo
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on February 19, 2018, 06:59:37 am
Hello,

@Ebel0410.
Thanks for the schema a power supply.
The symbol for 1n5819 and YG911S2 is not correct, it indicates a zener diode but it is a rectifying diode.

Regards,
Diabolo

The symbol is perfect, it indicates a Schottky diode, the Zenner is a bit different.

Schottky:
https://www.google.de/search?q=Schottky+symbol&num=50&client=ubuntu&hs=iUN&channel=fs&dcr=0&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwi-haa6s7HZAhVQyaQKHdY2AioQsAQIcg&biw=1855&bih=1102 (https://www.google.de/search?q=Schottky+symbol&num=50&client=ubuntu&hs=iUN&channel=fs&dcr=0&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwi-haa6s7HZAhVQyaQKHdY2AioQsAQIcg&biw=1855&bih=1102)
 
Zenner:
https://www.google.de/search?client=ubuntu&hs=5UN&channel=fs&dcr=0&biw=1855&bih=1102&tbm=isch&sa=1&ei=lHWKWqjIBczUkwWdq42AAQ&q=Zenner+symbol&oq=Zenner+symbol&gs_l=psy-ab.3..0i13k1j0i13i5i30k1j0i8i13i30k1l5j0i13i5i30k1.41765.42808.0.43591.6.6.0.0.0.0.121.487.5j1.6.0....0...1c.1.64.psy-ab..0.5.363...0j0i67k1j0i7i30k1.0.k5lvTbViCbA (https://www.google.de/search?client=ubuntu&hs=5UN&channel=fs&dcr=0&biw=1855&bih=1102&tbm=isch&sa=1&ei=lHWKWqjIBczUkwWdq42AAQ&q=Zenner+symbol&oq=Zenner+symbol&gs_l=psy-ab.3..0i13k1j0i13i5i30k1j0i8i13i30k1l5j0i13i5i30k1.41765.42808.0.43591.6.6.0.0.0.0.121.487.5j1.6.0....0...1c.1.64.psy-ab..0.5.363...0j0i67k1j0i7i30k1.0.k5lvTbViCbA)


 Cheers,
 DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 19, 2018, 07:32:09 am
Also added it to the git (https://github.com/DerKammi/FY6600-15-30-50-60M)

Here it is.
I don't have double checked all the components values.

This schematic shows the upgraded version I made by myself (the new values are in red).
The stock values are also mentioned.


(edited)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Diabolo on February 19, 2018, 08:13:39 am
Oops, sorry.
:palm:

Indeed, looking good symbols are correct.
I run to buy good glasses for my eyesight.

Diabolo
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on February 19, 2018, 07:06:48 pm
@Ebel, the relais routing is a bit strange to me as the common contact looks weird up until now. If you can draw that out that would help me. A photo from a paper drawing is fine.


Hi DerKammi,

I'll start working on that next weekend, hard stuff  :palm:
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 19, 2018, 07:09:57 pm
Don't worry, I soldered loose some relays of my board just 10 minutes ago and all is clear now.

And offcourse, it makes perfect sense when you see it :) As always. I'll post a small update of the schematics this evening to you show
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 19, 2018, 09:03:27 pm
Here is the schematic update. Onto the digital part.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Vytautas on February 20, 2018, 07:27:43 pm
Here, another guy posted what happened to his fy6600. It seems to be bricked. Though, no details are provided.
https://www.youtube.com/watch?v=a3v9sGDVfMI (https://www.youtube.com/watch?v=a3v9sGDVfMI)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 20, 2018, 07:36:28 pm
This is what typically happens if the CPU on the front board does not get any contact with the FPGA on the mainboard.

Like when you disable the FPGA because you are reading the WInbond, or if the cables between FB and MB are loose or broken.
Someone else reported a device was shipped with a loose cable, also looked like this.

I'd suggest to check the internal cables and their connectors.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 20, 2018, 07:46:35 pm
Like this:
https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1415538/#msg1415538 (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1415538/#msg1415538)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on February 21, 2018, 12:47:34 pm
My 6600 arrived  , V3.2
I swapped out the powersupply for something slightly better ,although the stock item seems to have been improved a bit ,it now has 25 volt low esr caps on the 12volt rails ,and the yellow x cap, 1mohm ,and slot by the opto are back ,its on a fibreglass board marked Feeltech V1.1

I have a transformer 2x17v and 8v which I will try later once the linear regulator board arrives .

I changed the dial on the encoder too ,the original is a bit small for the fingers to grasp.

I dont like the way the heatsink is mounted on the output Ic's ,due to a difference in height it doesnt seem to make good contact , I have two 3095 output ic's ,so I'll sort the heatsink out when I get those soldered in .

I tried the version 5.5 software ,one weird thing was that it seems not to respond when I switch on or off the channels via the front panel ,not sure if this is only one way communication here.

I still have to do some proper tests to check voltage and frequency cal .
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on February 21, 2018, 01:05:27 pm
Here's a photo with the upgraded PSU.
Slightly higher current and extra caps and inductors on the +/- rails .
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DaveR on February 21, 2018, 03:49:21 pm
Here's a photo with the upgraded PSU.
Slightly higher current and extra caps and inductors on the +/- rails .

Maybe it shows that Feeltech are taking note of, and acting on, what's being discussed on here - even though they're not letting on?  I bet they are taking a keen interest in the reverse engineering developments, with a view to a future model!
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DaveR on February 21, 2018, 03:55:26 pm

I tried the version 5.5 software ,one weird thing was that it seems not to respond when I switch on or off the channels via the front panel ,not sure if this is only one way communication here.


Yes, I noticed the same thing.  I could have sworn v5.3 was two-way, but maybe it's a false memory.  I'll try reinstalling the earlier version and get back to you.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on February 21, 2018, 10:16:39 pm
Hi Dave ,
The pic above is another +5-12+12 supply pulled from a dvd player ,
It has inductors on all the rails ,and a second smoothing caps after ,I even seen some switch modes with two inductors and three caps at the output of each rail .
Some reported that the caps on the feeltech psu 12volt rails were only 16 volts , the one I have has 25volt rated low esr caps at the outputs of each of the +/- ,only the 5 volt rail gets an output inductor and second cap ,also a low esr with 16 volt rating.

Either way when I turn up the output voltage of the generator it tends to pull down the 5 volt rail by a few hundred millivolts , theres likely some signal currents in the simple psu causing this interaction . Most decent equipment you find with switchmodes follow them with 78/79 type regs so noise is mV on the rails .Someone also suggested screening of the switchmode ,as there well known for radiating RF mush into other parts of the circuit . Im kinda just working through improving switchmode performance now ,but ultimately I'll most likely go old school Transformer/linear regulator later ,of course this presents its own electromagnetic screening issue which is expensive and difficult to reduce,upside is no rf problems.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DaveR on February 22, 2018, 04:58:36 am

Hi soundtec - the software IS two-way, but not constantly: if the FY6600 is on when the software is started the settings on the generator are read into the software, but after that they are read only when the "Load" button at the right of the program window is clicked.  That must be what I half remembered from the two or three minutes I played with it a few weeks ago.

You've got me thinking now about alternative power supply sources, as I've got a decent quantity of old satellite receivers and dvd players / recorders stashed in the loft.  I think I'll have to open them up and see what useful bits I can scavenge from them.  Most of them were top quality models when I bought them, so there may be some hidden gems to unearth, with a bit of luck.

Dave
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Scratch.HTF on February 22, 2018, 09:27:43 am
With regard to the circuit at Reply #791: at the THS3002 amp, the gain figure is 3.986 with a 10K input termination resistor and 4.006 without this resistor; changing this resistor to 33K results in a 3.999951 gain factor which is very close to a perfect 4.
Notably, the sine filter is not switchable and that there appears to be no frequency compensation including through full scale DAC current control for high frequencies.
To preserve waveform fidelity without the need to change waveform data depending on the output level range, the output levels are set by controlling full scale DAC current via its external voltage reference pin which the level is set by an auxiliary DAC.
There is significant jitter at output frequencies which have a division ratio at anything other than an integer against the DAC clock (fixed at 250 MHz) e.g. 250 MHz / 50 MHz = division of 5 has no jitter under ideal conditions while 250 MHz / 40 MHz = division of 6.25 has significant jitter (1.6 MHz).
I still don't know why the DAC clock is fixed at 250 MHz... an Arduino bootloader could be customized for the ARM microcontroller so that we can load custom firmware easily.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on February 22, 2018, 10:32:33 am
Thanks for that info Dave,

Ive been researching quietening switchmode psu's, assuming you have enough voltage to spare just adding a linear regulator after may not have much effect on high frequency noise ,LC filters ,both common and differential mode are a good idea though .

One benefit of the switcher is that it can withstand short term(100ms) drop outs in the mains supply and still maintain its voltage across the load, where a linear will certainly drop out with even something like 10ms duration of a mains fluctuation.
This might be important for the 5 volt rail ,less of an issue for the +/- 12 volt supplies on the op-amps I would imagine.
Would be interesting to hear from someone with design experience with switchmodes.                             
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 22, 2018, 03:28:07 pm
With regard to the circuit at Reply #791: at the THS3002 amp, the gain figure is 3.986 with a 10K input termination resistor and 4.006 without this resistor; changing this resistor to 33K results in a 3.999951 gain factor which is very close to a perfect 4.
Notably, the sine filter is not switchable and that there appears to be no frequency compensation including through full scale DAC current control for high frequencies.
To preserve waveform fidelity without the need to change waveform data depending on the output level range, the output levels are set by controlling full scale DAC current via its external voltage reference pin which the level is set by an auxiliary DAC.
There is significant jitter at output frequencies which have a division ratio at anything other than an integer against the DAC clock (fixed at 250 MHz) e.g. 250 MHz / 50 MHz = division of 5 has no jitter under ideal conditions while 250 MHz / 40 MHz = division of 6.25 has significant jitter (1.6 MHz).
I still don't know why the DAC clock is fixed at 250 MHz... an Arduino bootloader could be customized for the ARM microcontroller so that we can load custom firmware easily.

Thanks for the 33k resistor change. Like those small changes which help in make this device a little bit better every time.

Together with the adj. resistor we can actually "calibrate" the unit pretty nicely.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 22, 2018, 07:28:26 pm
I still don't know why the DAC clock is fixed at 250 MHz... an Arduino bootloader could be customized for the ARM microcontroller so that we can load custom firmware easily.

These are two separate topics right? (unsure because they are in one sentence)
Assuming indeed they are two topics:

Fremen67 already discussed the possibility to STMduino (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1419584/#msg1419584) this. But alas, the needed pins for the default arduino sketch upload (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1419673/#msg1419673) are used for other purposes on the FB, as are the ones for the serial uploader. We would be stuck using a STlink, even for the STM32duino code. So no easy upload, and thus we may as well burn firmware without loosing space to a bootloader (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1419841/#msg1419841).
Anyway, STlink is also easy, so not worry about it too much.


Not discussed here, but I did also think about changing frequency on the DAC to work around 4ns quantization jitter from a theoretical point of view.
But that is not so easy. PLL's typically have fixed ratio's, so even if you add more ratio's, you increase the number of perfect integers, but they are still among a sea of jittery real numbers.

Right now the FPGA is hard coded on a 50MHz x5 PLL. Even if we were to start tweaking the FPGA as well as the STM, I suspect we could only get fixed ratio;s. x4. x4.5 x5.
It would give us more points with no jitter, but still not all of them.

In my opinion, we'd need a VCO instead of a XO+PLL to get full variable clock and avoid quantization jitter, but it would give back classic jitter and frequency drift instead.




Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Val on February 22, 2018, 09:38:20 pm
Output frequency calibration.

It is possible that I missed a similar discussion before.

Many people complain about frequency accuracy and stability of FY6600.
After about 20-30 min frequency is relatively stable, but a reference oscillator lacking accuracy. My generator, for example, has 50,000,215 Hz reference frequency. It is no means to adjust this oscillator.

At the same time FY6600 allows for the output frequency calibration by firmware using the following procedure:

1.   Put the back main switch in “OFF” position.
2.   Press simultaneously “Power” and “CH1” buttons on the front panel and put the back main switch in “ON” position.
3.   Waite 3-4 seconds and release both front buttons.
4.   On CH1 select the highest output frequency for your generator model. Set an amplitude of 0,3-1,0 V.
5.   Press “SYS” and then “More”.
6.   Now on the screen you can see “Oscillator” and on display 10.000.000.000 MHz
7.   Press F5 to go to frequency calibration.
8.   Connect a frequency meter to CH1 output.
9.   Using cursor and the dial obtain reading of the frequency meter the same as set on the generator. If measured frequency is lower – dial should be rotated CCW, if higher – CW.

After calibration press the “Dial” and then CH1 to return to normal operation.
73, Val
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on February 22, 2018, 10:25:37 pm
Thanks for that Val ,
Ive been through every inch of this topic and I can't recall any internal cal procedures like that mentioned before ,How did you find out about it ? and is there anymore hidden menus?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on February 22, 2018, 11:32:37 pm
Even though I have no very accurate frequency meter (60,000 counts),I could certainly see that the unit needs some time to stabilize after switch on ,its the same for almost all electronics really ,takes time for the temps inside the case to level out ,its always a good plan especially with test gear to allow a warming up period before attempting to calibrate.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 23, 2018, 06:16:23 am
@Val, That's a great first post in this topic. How do you know this stuff? Any manual we don't know?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 23, 2018, 07:45:28 am
Output frequency calibration.
....

Wow. It actually works.
I was very suspicious and even checked the calendar (not April 1) before trying this, but there actually is such calibration option.

Many thanks for showing us. But also, how did you know? Any other tricks?


However, I feel such calibration would in fact increase the quantisation jitter, because of the fixed 50Mhz x5 clock. So they would have to drop/add a tick every so often.
Remember ArthurDent who replaced the 50MHz XO with a OCXO (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1346454/#msg1346454) and got 10 digits of correctness on his frequency, proving the FPGA logic itself is dead on, and its all about the crystal it uses.
Also, this would not fix the temperature drift as the device heats up. Even blowing on the XO (cooling it) showed a visible drift and back as it cooled and then heated back up

I'd have to test this, if it actually indeed increases jitter.
So if frequency is important to you, especially above lets say 5MHz or so, a better method might be to leave this alone and replace the XO with a better and cheap and easy TCXO or even OCXO


But I do want to repeat this is a amazing find. Wherever/However you found this, what else do you have for us?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DaveR on February 23, 2018, 04:07:21 pm
This is indeed a very useful trick to know, and its existence shows that there's probably a few other hidden engineering functions buried in the firmware.  I'm not too fussed about the frequency accuracy as mine is close enough for my needs, but I'd love to know if there's a way to equalise the amplitudes on each channel to get rid of the small difference I see.  I know there are four little trimpots inside which can be adjusted, but my experience with those things is normally that you can spend an hour tweaking them backwards and forwards without ever hitting the right spot, and if you do it will still need redoing the next time you switch on.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Val on February 23, 2018, 09:26:46 pm
Dear Soundtec,

As they say: If you do not knock - nobody opens a door.
It was very simple: I asked FeelTech.

73, Val
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: bitseeker on February 23, 2018, 09:30:55 pm
It was very simple: I asked FeelTech.

Hehe. Welcome to the forum, Val.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Ebel0410 on February 23, 2018, 11:07:46 pm
Thanks Val, your post is very usefull !
Actually, a question came up to my mind.
Is there a procedure to adjust other values ? I guess the answer is certainly positive..
And then, all of these parameters are probably stored in the flash memory, but where ?

It's like looking for a needle in a haystack.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on February 24, 2018, 02:47:41 am
A ten turn pot on amplitude adjustment on each channel would be nice ,I notice a few tens of mV difference between ch1 and ch2 on my unit ,its awkward to try and fine tune things with single turn micro pots.

Maybe we have underestimated Feeltech's willingness to engage in terms of the product feedback were offering up here ,'ask and you shall receive' is the saying that springs to mind ,'God helps those who help themselves' is another.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on February 24, 2018, 02:52:18 am
Dont worry by the way ,I'm not some religious nut trying to convert you all with biblical quotes  >:D
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Insatman on February 24, 2018, 03:06:09 am
Replacement of 50Mhz clock chip with TCXO (1ppm).   

Greetings.  Yesterday I swapped out my Feeltech 6600 50Mhz IC with a DJ75-050.0M IC.  The DJ75 has a 1ppm per year aging spec as well as 1ppm frequency stability vs temperature.   It has 10 pads of which only 4 are used.  You must connect pads 8 and 9 in this application.  Fortunately they pretty much line up with the existing pads on the Feeltech 6600.   Please excuse my lousy SMD soldering skills in the photos.  Results were good.   After installation I let the unit run overnight to reach thermal equilibrium.  Then I followed the frequency calibration procedure provided by Val (thanks again!).   Results were spot on measured over a couple of hours.  My counter was locked on 60Mhz where the FT6600 was set. 

The DJ75-050.0M is available from Digikey for about $11 US.   Datasheet attached.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: rhb on February 24, 2018, 04:07:52 am
Dear Soundtec,

As they say: If you do not knock - nobody opens a door.
It was very simple: I asked FeelTech.

73, Val

And didn't ask them to fix a borked unit.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: paulca on February 24, 2018, 08:11:25 am
So I ordered one of these.  Waiting on delivery.

I scan read the thread.  It's cheap, has some minor issues, that's fine.  The only current use case I have is testing circuits in the audio range, maybe testing a few ultra sonic filters.

Can anyone explain to me if the PSU issues are safe or do I really need to replace it?  If I do need to replace it, would a PC PSU do the job, it has +-12V and +5V obviously.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Insatman on February 24, 2018, 10:12:54 am
So I ordered one of these.  Waiting on delivery.

I scan read the thread.  It's cheap, has some minor issues, that's fine.  The only current use case I have is testing circuits in the audio range, maybe testing a few ultra sonic filters.

Can anyone explain to me if the PSU issues are safe or do I really need to replace it?  If I do need to replace it, would a PC PSU do the job, it has +-12V and +5V obviously.

The unit is basically safe for humans but the "ground" of the BNC will measure about 1/2 of your AC voltage into a high impedance.  The current is small but can be felt as a tingling in some situations.  This could cause problems with sensitive electronics in some situations.  The problem is that they use a two terminal AC input connector so there is no earth ground reference.

Just add three terminal ac input with ground or, like me add a separate banana jack to ground the unit to earth.  This will prevent the outer of the BNC connectors from having any AC on them.

The advantage of the banana jack is that you can easily disconnect it if you wish to float your function generator above ground for some special circuit.   
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: paulca on February 24, 2018, 12:31:16 pm
Is there an easy to source alternative to replace the PSU inside?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 24, 2018, 01:41:48 pm
For some reason I'm thinking that there would be some interest for a self designed linear PSU. Just an idea.

@Fremen67: not wanting to push, but do you have any homework for me yet? My ST-Link clones arrived yesterday and are upgraded to the latest firmware. So time to flash these units :D
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: paulca on February 24, 2018, 02:11:06 pm
For some reason I'm thinking that there would be some interest for a self designed linear PSU. Just an idea.

Interesting.  But it would be my first mains fed PSU.  Makes me re-read my signature.

EDIT: any idea on the current requirements of it?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 24, 2018, 02:34:44 pm
Don't worry. Have one ready from another project. Can be easily made smaller for the space available.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on February 24, 2018, 04:00:30 pm
@Fremen67: not wanting to push, but do you have any homework for me yet? My ST-Link clones arrived yesterday and are upgraded to the latest firmware. So time to flash these units :D
I had a busy week at work. It seems it's always like that when you want to take some days off  :)

I get stucked in my tests with the Feeltech PC Software. I though it would last longer without any modification but I was too optimistic...
When you type 123.45 Hz, it sends 1 then 12 than 123 then .... Hard to trigger anything correctly when debugging...

So long story short: I made some modifications to the PC Software:
- Add an input box to handle more easily inputs
- Remove all the amplitude & offset modifications the software was doing (the FP already handles that)
- Read back of parameters that the FP could change (Amplitude & Offset)
- Read back of CH2 synchronized parameters when changing CH1 parameters
- Add Synchrone Reads & Writes
- fixed the regional setting issue with "," & "."
- Add a Refresh button, just in case you modify things directly on the FG
- modified the display setting...

The source posted by feeltech was not the latest as you will see (mainly arbs handling differences) but it doesn't matter at the moment

If you already installed the original Feeltach software, you just have to copy and launch the modified one.

Could some of you guys try it ?

Now that the parameters are read from FG, I noticed that negative offset are not sent correctly by the FP. It is sending out of range values. I just display 0 in the case.

So I can go back to FP firmware now  :box:

Edit: Oups! Wrong file. OK now  :P
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on February 24, 2018, 04:13:49 pm
@fremen67: I have a small question, do we really need to change the parameters fully to change just one, or for example the frequency can be changed by just one register operation or register operation + reload registers trigger, so just 2 register write, I'm curious haw fast one can sweep the frequency/phase ?
Sorry I missed your question. No you don't need to send all the parameters each time. No trigger required except fot the phase. So just one register write most of the time.
I don't know the change speed limit for now. I will see this when programming the sweep function. Not sure this will be the comming week. I first have to finish the basic functions.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on February 24, 2018, 04:22:29 pm
Here is the schematic update. Onto the digital part.
:-+ Well done.
I think we will have a problem to solve with the outout impedance. It's 50 ohms for the medium and high output range ... but not for the low output range ...
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on February 24, 2018, 04:34:24 pm
Output frequency calibration.

It is possible that I missed a similar discussion before.

Many people complain about frequency accuracy and stability of FY6600.
After about 20-30 min frequency is relatively stable, but a reference oscillator lacking accuracy. My generator, for example, has 50,000,215 Hz reference frequency. It is no means to adjust this oscillator.

At the same time FY6600 allows for the output frequency calibration by firmware using the following procedure:

1.   Put the back main switch in “OFF” position.
2.   Press simultaneously “Power” and “CH1” buttons on the front panel and put the back main switch in “ON” position.
3.   Waite 3-4 seconds and release both front buttons.
4.   On CH1 select the highest output frequency for your generator model. Set an amplitude of 0,3-1,0 V.
5.   Press “SYS” and then “More”.
6.   Now on the screen you can see “Oscillator” and on display 10.000.000.000 MHz
7.   Press F5 to go to frequency calibration.
8.   Connect a frequency meter to CH1 output.
9.   Using cursor and the dial obtain reading of the frequency meter the same as set on the generator. If measured frequency is lower – dial should be rotated CCW, if higher – CW.

After calibration press the “Dial” and then CH1 to return to normal operation.
73, Val
Brilliant. Adjusting frequency sends new values to registers 0x25 to 0x2A which are used during start up  :-+
I don't know what is inside but we now have a way to find out.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 24, 2018, 05:14:16 pm
I will try tomorrow if all goes right this weekend. Family first off course.

Thanks for the effort nevertheless.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 24, 2018, 05:16:36 pm
That could mean a way with a lookup table minimize jitter perhaps?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Insatman on February 25, 2018, 03:13:21 am
Is there an easy to source alternative to replace the PSU inside?

I found a nice small switching supply on Digikey for about $38 that would both fit and work nicely.  But you would still have to add the three terminal AC socket to fix the AC leakage problem.  In the end I decided against it, opting instead to simply upgrade the output capacitors and add a lossy ferrite core to the output cable to damp the switching noise.   I never observed the large swings on the +/- 13V rails that other's have observed.  My 5V rail puts out almost 5V exactly.   These mods only cost a few $ as opposed to $38 which more than 1/2 the cost of the 6600 anyway.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on February 25, 2018, 04:47:11 am
Yeah spending 50% of the cost of the unit on upgrading the psu doesnt make any sense , I happened to find a clapped out dvd player with a psu with the appropriate rail voltages though . 10 quid 1:1 isolation transformer as found in a shaver panel socket fixes the leakage problem nicely too .

I was thinking, another way to help with bit munching digital attenuation would be to make an old school switchable attenuator and putting it across the output ,and just run the outputs balls to the wall full on ,might well improve the THD levels especially at smaller output signal levels .

I downloaded Fremens special software package too  ,looks very promising ,tomorrow I'll give it a whirl hooked up to the unit and report back ,I also noted the spelling of 'Control' was fixed in that window ,something that caught my eye the first moment I loaded the original Feeltech app .

I got two of the TI 3095 op amps mentioned way back in this topic ,would a recalculation of the feedback resistor be required here in order not to upset voltage scaling ?

Shoehorning in some ten turn preset pots on the amplitude adjustment might be a good plan too ,its fiddly to try and accurately adjust single turn micro presets ,where ten turns would allow us to trim things very much more accurately .

What really makes this project for me is that we've drawn in expertise from every corner of the globe ,and were suceeding in making a humble box of tricks into something which punches well above its weight and learning tons about whats going on under the hood in the process.
 
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Insatman on February 25, 2018, 04:54:22 am
Channel 2 Output waveform intermittent distortion.

check out this on Ch2 of my FY6600.  Channel 1 does not have this problem.  Any suggestions?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: paulca on February 25, 2018, 08:51:47 am
Yeah spending 50% of the cost of the unit on upgrading the psu doesnt make any sense

Unless it's fun.

Mains leakage scares me.  I don't like the sound of it or the responsibility to understand when it will and when it won't blow stuff up on me.

Like if I want to test a 3 channel mixer breadboard, 2 channels from the FY6600 and one channel from my phone which it's connected via USB to earth ground.  I'd rather not smoke my £300 phone! :)

I still have a unpopulated spot on my EE jumper where the "Built my own PSU" badge goes.  Building a linear mains +-12V +5V supply sounds like a nice project.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Insatman on February 25, 2018, 09:02:15 am

I still have a unpopulated spot on my EE jumper where the "Built my own PSU" badge goes.  Building a linear mains +-12V +5V supply sounds like a nice project.

Will there you go!   Finding transformers you like are usually the hardest part.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: paulca on February 25, 2018, 09:05:07 am

I still have a unpopulated spot on my EE jumper where the "Built my own PSU" badge goes.  Building a linear mains +-12V +5V supply sounds like a nice project.

Will there you go!   Finding transformers you like are usually the hardest part.

Yes.  That and when you look up "How do I pick a transformer" I realise I also lack the "I understand calculus" badge. :(  AC sucks.

The whole VA rating thing might as well be Voodoo to me.  I'm left looking for transformers that have a "Maximum secondary current" spelled out in the datasheet.

Finding a multi-secondary to provide 2x12V + 1x5V seems a next to impossible to.

Probably need another thread in Beginners, but... can I not just drop the +12V side down to 5V with a reg?  Can I just series the 2x12V from the transformer and take the centre point at common?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on February 25, 2018, 09:31:06 am

I still have a unpopulated spot on my EE jumper where the "Built my own PSU" badge goes.  Building a linear mains +-12V +5V supply sounds like a nice project.

Will there you go!   Finding transformers you like are usually the hardest part.

Yes.  That and when you look up "How do I pick a transformer" I realise I also lack the "I understand calculus" badge. :(  AC sucks.

The whole VA rating thing might as well be Voodoo to me.  I'm left looking for transformers that have a "Maximum secondary current" spelled out in the datasheet.

Finding a multi-secondary to provide 2x12V + 1x5V seems a next to impossible to.

Probably need another thread in Beginners, but... can I not just drop the +12V side down to 5V with a reg?  Can I just series the 2x12V from the transformer and take the centre point at common?

Hello, let me help you, first but this trafo, it has all you need:
https://www.ebay.de/itm/Netztransformator-230V-8V-1-7A-4-2V-0-15A-13-6Volt-2x0-6A-Mittenanzapfung-NEU/152891642048 (https://www.ebay.de/itm/Netztransformator-230V-8V-1-7A-4-2V-0-15A-13-6Volt-2x0-6A-Mittenanzapfung-NEU/152891642048)

Second, of course you can use the 12V and put a linear regulator to make 5V out of it, but it will be a horrible design, for every 1W on 5W, you're wasting 2W of heat, that will make the nerd Baby Jesus cry  :'(.

So, get yourself this trafo, 2 rectifier bridges, one 4700uF/16V, 2 x 2200uF/35V, 3 tantalums of 1uF/35V, even 3 x 0.1uF, one 7815 (+15V), one 7915(-15V) and one 7805 and carefully place them on radiators and you're done, the PCB can be a piece of breadboard, after all is tested, carefull unsolder the original connector or buy a ne one and connect the cable. Fertig !!!
NOTE: If you're using +/-15V you may want to replace the 16V capacitors from the signal board, if you want to use 12V replace 7x15 with 7x12.

 Cheers,
 DC1MC 
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Insatman on February 25, 2018, 09:46:02 am

I still have a unpopulated spot on my EE jumper where the "Built my own PSU" badge goes.  Building a linear mains +-12V +5V supply sounds like a nice project.

Will there you go!   Finding transformers you like are usually the hardest part.

Yes.  That and when you look up "How do I pick a transformer" I realise I also lack the "I understand calculus" badge. :(  AC sucks.



The whole VA rating thing might as well be Voodoo to me.  I'm left looking for transformers that have a "Maximum secondary current" spelled out in the datasheet.

Finding a multi-secondary to provide 2x12V + 1x5V seems a next to impossible to.

Probably need another thread in Beginners, but... can I not just drop the +12V side down to 5V with a reg?  Can I just series the 2x12V from the transformer and take the centre point at common?

You don't really need calculus for this.   In this application you need +/- 13 VDC and +5 VDC.   The +5 needs to be stiffer (in terms of current) than the 13V rails.  If you were to drop down from a +13 volt rail you would be wasting a lot of power and loading that rail much more than the negative rail.  This likely drives up the transfomer size more than necessary.   Most of the designs I've seen for this particular application use two transformers.  A center-tapped 2x12 or 2x15V for the +/- 13 VDC and a 8 or 10V transformer for the 5V rail.  If you can find a multiple secondary transformer that is ideal of course.   If you can find them in your junk bin the right size great.

Using Digikey as an example source, there are no transformers I can find with the three wingdings desired.  So that leaves a CT 12 or 15V and separate 8 or 10V transformer. 
My FY6600 draws less than 10W.  So we can use pretty small transformers here.   Looking at the PS board of the FY6600 would guess the 13V rails are a small fraction of an amp each and the 5V rail maybe approaching an amp at most.   Since the size of the transformer does not scale linearly with cost, it's safest to oversize them somewhat if you have space.  This keeps them cool and lets you sleep easier.

For the +/-13 V rails the Triad FS24-500-C2 is rated at 500mA for each of it's dual secondary windings.   If you series the primaries you can use 230V in England  (240 would also work).  This transformer is rated 50/60Hz.   For the 5V rail the Triad VPP20–1000 is rated at 1A using both it's 10V secondaries in parallel.  You series the dual primaries as before for operation at 230/240 50/60Hz.  Both of these transformers are PC board mount (mount on perf), but you can find flying lead versions easily but likely cost a bit more.   Other companies offer equally good units.  Each of these cost about $12 or so.   

I also see just as I'm posting this that another member has posted an Ebay link to a multiple secondary transformer on Ebay at a very good price.

Good Luck

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 25, 2018, 09:59:29 am
"Versand: Möglicherweise kein Versand nach Niederlande"
I am assuming the same for UK

@paulca
Does your local municipal recycle centre allow you to browse/takeback  brown goods?
Mine does not anymore, so you have to be sneaky. (they claim they can be held responsible if they allow people to take back faulty stuff)

But if so, typical non-digital era audio amplifiers/preamps have transformers in them that have +/- 15 V for the amp stuff, as well as usually a 12V or 6V rail for auxiliary stuff.
Or you can spend money and get those new (https://www.ebay.com/sch/i.html?_from=R40&_sacat=0&_nkw=r-core+transformer&_sop=15), but personally I always feel extra pride/smart/aware by repurposing old stuff.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on February 25, 2018, 10:02:36 am
"Versand: Möglicherweise kein Versand nach Niederlande"
I am assuming the same for UK

@paulca
Does your local municipal recycle centre allow you to browse/takeback  brown goods?
Mine does not anymore, so you have to be sneaky. (they claim they can be held responsible if they allow people to take back faulty stuff)

But if so, typical non-digital era audio amplifiers/preamps have transformers in them that have +/- 15 V for the amp stuff, as well as usually a 12V or 6V rail for auxiliary stuff.
Or you can spend money and get those new (https://www.ebay.com/sch/i.html?_from=R40&_sacat=0&_nkw=r-core+transformer&_sop=15), but personally I always feel extra pride/smart/aware by repurposing old stuff.

Drop a mail to the seller, you'll find understanding, in the worst case I can act as "relay" if anybody wants it.

 Cheers,
 DC1MC
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 25, 2018, 10:43:13 am
Output frequency calibration.
...

Brilliant. Adjusting frequency sends new values to registers 0x25 to 0x2A which are used during start up  :-+
I don't know what is inside but we now have a way to find out.

That could mean a way with a lookup table minimize jitter perhaps?

So, just in case I was wrong about my "unmuteable fixed clock and PLL" theory, I did some tests.
Alas, correcting the frequency does not actually change the frequencies jitter.
For example, normally 10MHz square is perfectly jitter-free, due to being a perfect divider of 250.

Correcting it to 9.900000 cause the jitter to appear on 10MHz (which is now actually 10.010101MHz), and 9.900000 (which is now actually 10.000000) still is jitter free. To me that shows they are not changing the clock, just count more or less ticks of it, and the jitterfree points stays fixed on the frequencies as they are dividable on the 250MHz clock.
So I see no way how we can use this to reduce the jitter issue.

While it does not make the jitter worse, it does make it less predictable / less easy to calculate.
For example, if you were to set a realistic correction value of 9.999982, you'd get these jitterfree values:
(https://i.imgur.com/Keqy06h.png)
I often use some of these, usually not because the jitter actually matters to the circuit, but mostly because the scope screen is easier to read without those annoying double lines.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: paulca on February 25, 2018, 10:52:34 am
Thanks.

I tried every search under the sun on ebay and it never shows me transformers I want.  That r-core search showed loads.  I conclude that ebay search is rubbish.  How come "Transformer 2 x 13 VAC" doesn't find anything, but there are literallly hundreds of r-core transformers with 2 x 13 VAC in the title... and the related items show non r-core transformers with similar outputs.  Grrr.

What about something like this:
https://www.ebay.co.uk/itm/1x-220V-30W-R-Core-Transformer-R-TRANSFORMER-for-stereo-DAC-board/151254842393?hash=item23377dbc19:g:n1AAAOxyf1dTJG-G (https://www.ebay.co.uk/itm/1x-220V-30W-R-Core-Transformer-R-TRANSFORMER-for-stereo-DAC-board/151254842393?hash=item23377dbc19:g:n1AAAOxyf1dTJG-G)

2x15V 2x9V 30W

Of course the next challenge is learning how to wire it up without blowing stuff up while trying to work out how to series the primaries for 230V and parallel the 2x9V secondaries for 0-9V.  I understand if I short a secondary the fuse, nor RCD will help keep the smoke in.

I'm keen, but maybe out of my depth... although sometimes the deep end is the best place to learn to swim.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: paulca on February 25, 2018, 10:59:43 am
I tried every search under the sun on ebay and it never shows me transformers I want.  That r-core search showed loads.  I conclude that ebay search is rubbish.  How come "Transformer 2 x 13 VAC" doesn't find anything, but there are literallly hundreds of r-core transformers with 2 x 13 VAC in the title... and the related items show non r-core transformers with similar outputs.  Grrr.

Ooops, I was stuck in a sub category.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 25, 2018, 11:25:30 am
From memory, I recall under 200mA or so on the 12V and under 400mA or so on 5V. So 6~7W total.
Linear would waste a bit more but 10W should be enough.

So that 30W does seem a bit overpowered, but then a again, a similar 10W model (https://www.ebay.com/itm/282415016375) is almost the same size.
The one DerKammi DC1MC found is actually slightly smaller still, and at €4.5 pretty cheap, if you manage to get it into the UK at not too much extra cost.

As to wiring. Well, that's petty basic. Good thing about about transformers is they usually take a few seconds, even at a short, before they start releasing smoke.
Simply put a slow 0.1A fuse (https://www.ebay.co.uk/itm/170776131200) on the 240V side if you feel anxious though, that should go with a 30W short.



Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: paulca on February 25, 2018, 12:05:02 pm
Well I bought the german ebay one, but I have to ask the seller if they will ship the UK.

I put the request in English and Googlese German:

Können Sie an eine britische Adresse versenden?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DC1MC on February 25, 2018, 12:11:17 pm
Well I bought the german ebay one, but I have to ask the seller if they will ship the UK.

I put the request in English and Googlese German:

Können Sie an eine britische Adresse versenden?


Good idea.
Shipping with DHL is 8.89EUR without tracking and 13,99EUR with tracking. The seller shouldn't do anything special, except buying an international shipping label from the same EBAY page where it buys its German ones.
Now collect the other parts as well and you're done.  8)
 Cheers,
 DC1MC - "Waiting in a fetal position to get a power n-mos from a kind German soul, but none so far :("


Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 25, 2018, 01:27:37 pm
Not sure if it would break your "badge earning rules" but to complete it, have you seen these (https://www.ebay.com/itm/322598834251)

I kind of agree you need to build your own at least once (did mine 30+ years ago), but boy, for $3 I can barely even pick up the needed 7805/7812 at the local component shop.
(also, all local component shops either perished, or are only selling complete gadgets and drones nowadays)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DaveR on February 25, 2018, 02:00:32 pm
Not sure if it would break your "badge earning rules" but to complete it, have you seen these (https://www.ebay.com/itm/322598834251)

I have a couple of those, cybermaus (15v and 12v), and the ouputs are not very well balanced (something like +12.0, -12.7 on the 12v model).  When I made my linear I went for the variable voltage version so that I could ensure that the outputs were balanced, and also to give flexibility to increase the outputs up to +/-15v if a future mod should require it.  The board is a lot bigger, but it still fits nicely in the case with a 15v/9v r-core transformer (as you can see from the photo I posted a couple of pages back).

If you want to build your own, it's still cheaper to buy the kits from China to get the parts, then do your own layout on Veroboard.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on February 25, 2018, 02:42:20 pm
The CMOS function allows negative offset. Did I miss something or is the CMOS function supposed to be always positive?

I think this could also be usefull to foresee a minimum and a maximum output parameter when connecting sensitive DUT...
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: paulca on February 25, 2018, 02:59:45 pm
Thanks for the help guys.  I will move the discussion on building my PSU to the Beginners's forum shortly.  Don't want to pollute the product thread.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 25, 2018, 04:00:03 pm
Tiny update from my side
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 25, 2018, 04:25:51 pm
Is the CMOS not just simply a quick way to set a signal level square?
Possibly the only special thing is: If you increase Vpp, it does not dive negative.

Whereas if you make your own 3.3Vpp 1.65Voffset square, and increase to 5Vpp, it would accidentally go negative first, before you remembered to also change offset to 2.5V
(I have had that problem, luckily my DUT survived)


But to be honest: I feel all waveforms should consider that 0V case. If I have a Vpp and Offset such that Vbottom is 0V or even positive, then merely changing Vpp should not make it negative. Or some sort of boundary setting. (edit, reading back, I realize you were saying the same)

Right now, the only waves that are bottom based are I think CMOS, half-sine, rectified-sine (and of course, negative half-sine is top based)
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 25, 2018, 04:38:16 pm
I have a couple of those, cybermaus (15v and 12v), and the ouputs are not very well balanced (something like +12.0, -12.7 on the 12v model).  When I made my linear I went for the variable voltage version so that I could ensure that the outputs were balanced, and also to give flexibility to increase the outputs up to +/-15v if a future mod should require it.  The board is a lot bigger, but it still fits nicely in the case with a 15v/9v r-core transformer (as you can see from the photo I posted a couple of pages back).
Odd. They are 7912's, how are they able to mess that up?
I can only see that happen you had a bad 7912 itself. I guess that is possible

If you want to build your own, it's still cheaper to buy the kits from China to get the parts, then do your own layout on Veroboard.
Which then negates that. Maybe the other way around, buy a new local 7912 and solder it onto the chinese PCB.


Anyway. Anything is possible with these cheap things from eBay. Sometimes very good value, sometimes not even worth the space they take up in the garbage.
The only reason I keep buying it (when not in a hurry) is that if I buy local, it is also junk from china, just someone else did the ordering for me.


Unless if Mouser of course. But you know, €20 handling fee, always.
I do sometimes order with them, but not the small stuff.

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: paulca on February 25, 2018, 04:45:00 pm
The only reason I keep buying it (when not in a hurry) is that if I buy local, it is also junk from china, just someone else did the ordering for me.

Unless if Mouser of course. But you know, €20 handling fee, always.
I do sometimes order with them, but not the small stuff.

I agree.  The UK Ebay at the moment is unfortunately infested with Chinese seller with UK addresses, claiming the item location as UK, when it clearly isn't and takes 2 to 4 weeks to arrive if it ever appears.  You have to read seller names and addresses carefully to filter out the bad ones.

I don't order from Mouser, but RS Components or for a sizable order Farnell.  RS have free shipping and no handling charge for any size of order including a single 0.1p resistor technically.  Though you would feel like a bit of a dick doing that to them.

The downside I find is that for some components the price they leaves you running your hands under cold water cause you feel burnt.  Panel volt meters.  You can find pretty decent ones on Ebay for £5.  RS components, unless you want an analogue one they are in the £30-70 range!  There are many other examples. Breakout boards are fierce price too.  Even something mickey mouse like an SOIC-8 to DIP adaptor board is like £8 each!
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on February 25, 2018, 05:27:47 pm
Absolutely no need to be intimidated by the numbers when calculating power supplies Paulca.
Take your winding voltage ,multiply it by 1.4 ,now from this you have to subtract the losses across the diodes in the bridge ,then you'll still have to allow at least a few volts extra so that whatever regulator you have can function effectively without dropouts .
Google Duncans PSUd 2 ,thats a really handy little tool for mocking up your psu's before putting money into components ,after a few uses of this software you'll get a feel for what your doing and the intimidation factor will be a distant memory. The more voltage the regulator has to drop the bigger the heat sink will need to be  , also the more voltage drop across the reg also tends to give a quieter noise level at the output.
Best o luck.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on February 25, 2018, 06:03:12 pm
Is the CMOS not just simply a quick way to set a signal level square?
Possibly the only special thing is: If you increase Vpp, it does not dive negative.

Whereas if you make your own 3.3Vpp 1.65Voffset square, and increase to 5Vpp, it would accidentally go negative first, before you remembered to also change offset to 2.5V
(I have had that problem, luckily my DUT survived)


But to be honest: I feel all waveforms should consider that 0V case. If I have a Vpp and Offset such that Vbottom is 0V or even positive, then merely changing Vpp should not make it negative. Or some sort of boundary setting. (edit, reading back, I realize you were saying the same)
Yes security for the DUT was the point. In the new firmware, I have at least 3 options: either I just reset the offset when selecting CMOS (as a positive offset could also leads to destruction of the DUT) or I send a null offset when  the CMOS function is in use... or I just let it like this and this will be secured later on with min and max output parameters for all functions... The last one beeing my prefered ATM.
For the other bottom based functions, using the offset does not seem to be a problem.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on February 25, 2018, 06:52:59 pm
Tiny update from my side
Better each time :-+

May I suggest these modifications?

W16: DC_AMPL_CH2_OFFSET
W3: DC_AMPL_CH2_GAIN

W26: DC_AMPL_CH1_OFFSET
W5: DC_AMPL_CH1_GAIN
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 25, 2018, 06:55:25 pm
Choices, choices.....

I do feel that going from any wave to CMOS should avoid going over 3.3 (5) or below 0, unless you specifically set that.
But I also feel that having set Vpp and offset, and then walking from Sine to Triangle or so, should not loose your values because you happened to walk past CMOS

To be honest, I think apart from your idea to set an optional per channel DUT voltage safety window, when walking through the waveforms they should not immediately apply, but only after you confirm. So you can go from one wave to the other, without generating all the waveforms in-between. This is unlike walking through frequencies, which of course should immediately apply.


In fact, in the hope that FeelTech would pick it up, a good while back I already mentioned (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1335080/#msg1335080) that pressing the Wave button is auto-advancing, which is wrong anyway:
Right now, if I am on Square, and I want to go to Sine (one to the left), I always first have to go to CMOS (one to the right) and then go 2 back. Just plain silly.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: paulca on February 25, 2018, 07:17:49 pm
Absolutely no need to be intimidated by the numbers when calculating power supplies Paulca.
Take your winding voltage ,multiply it by 1.4 ,now from this you have to subtract the losses across the diodes in the bridge ,then you'll still have to allow at least a few volts extra so that whatever regulator you have can function effectively without dropouts .
Google Duncans PSUd 2.

Thank you.  The "time 1.4" thing leads me to ask "why 1.4" which leads to a rabbit hole.  But... I have seen it used enough without caveat that maybe I should just trust it.

I was also considering the drop on the linear regulators and thus aiming high for +-15V to provide +-12V as +-13VAC are hard to find.  Also once you factor in the drop across the recifier 13V will become 12.3 volts quickly. 

Different engineering, but in software when I can't calculate (or don't want to calculate) exact values, I just double the estimates to provide a suitable margin.

Going for +-15V for a +-12 rail through a transformer is not quite doubling, but lets not split hairs. :)

Quote
Best o luck.

You know in an odd way that makes a difference to a post.  I might have had half (+50% engineering grace) a bottle of wine, but for me it suggests you took to the time to actually care that I have luck and you weren't just show boating your knowledge.

The point of this post, having too much wine asides...

It's the VA rating that bothers me.  When a transformer says it has a rating of 6VA,  what does this actually mean in real terms?  Especially if you want to run a given DC load off it?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: fremen67 on February 25, 2018, 07:57:46 pm
Choices, choices.....

I do feel that going from any wave to CMOS should avoid going over 3.3 (5) or below 0, unless you specifically set that.
But I also feel that having set Vpp and offset, and then walking from Sine to Triangle or so, should not loose your values because you happened to walk past CMOS

To be honest, I think apart from your idea to set an optional per channel DUT voltage safety window, when walking through the waveforms they should not immediately apply, but only after you confirm. So you can go from one wave to the other, without generating all the waveforms in-between. This is unlike walking through frequencies, which of course should immediately apply.
So then we could go for a mix: Protection via min/max voltage (to be set before connecting the DUT...) and then anyway sending null offset (without loosing the value) when in CMOS.
But once activated,  over range voltage protection should not depend on the selected wave. Once your DUT is connected it should be protected whatever you could do.
In fact, in the hope that FeelTech would pick it up, a good while back I already mentioned (https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-function-arbitrary-waveform-signal-generator/msg1335080/#msg1335080) that pressing the Wave button is auto-advancing, which is wrong anyway:
Right now, if I am on Square, and I want to go to Sine (one to the left), I always first have to go to CMOS (one to the right) and then go 2 back. Just plain silly.
Yes indeed. You can imagine the following:
- 1 push on wave button: highlight wave selection (selection mode)
- another push on wave button: cancel selection mode
When in selection mode:
Turn rotary knob to go through waves without modifying the current one (wave plot having another colour to show selection mode active)
Confirm your choice by pushing the rotary knob..
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 25, 2018, 08:17:57 pm
Tiny update from my side
Better each time :-+

May I suggest these modifications?

W16: DC_AMPL_CH2_OFFSET
W3: DC_AMPL_CH2_GAIN

W26: DC_AMPL_CH1_OFFSET
W5: DC_AMPL_CH1_GAIN

That is why I post the small updates. Consider it done 😁
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: cybermaus on February 25, 2018, 08:37:39 pm
Yes indeed. You can imagine the following:
- 1 push on wave button: highlight wave selection (selection mode)
- another push on wave button: cancel selection mode
When in selection mode:
Turn rotary knob to go through waves without modifying the current one (wave plot having another colour to show selection mode active)
Confirm your choice by pushing the rotary knob..

Exactly. For the Wave.

For others, like frequency, a small variant:

- 1 push on freq button: highlight freq selection (selection-follow mode)
- another push on freq button: different color highlight (selection-confirm mode)
- yet another push on freq button: cancel selection mode, no more highlight.

When in selection-follow mode:
- Turn rotary knob to go through frequencies *with* modifying the frequency,
- As the frequency is set automatically, it stays the normal color

When in selection-confirm mode:
- Turn rotary knob to go through frequencies *without* modifying the current one
- As the frequency is not set, it stays the special UNSET color
- Confirm your choice by pushing the rotary knob, now color returns to the SET color, until you turn the rotary again.
- Canceling your choice (by pressing freq button again, while color is the UNSET color, displays the original frequency and non-highlighted color


So while we have 2 modes for frequency (follow and confirm) and analogue the wave has only one mode (confirm), I would argue for frequency the follow mode is the first one, whereas for wave the confirm mode is the first (and actually only) one.

Amplitude and Offset may also have similar follow and confirm modes, so you can either jump from one to the other, or walk to it.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on February 25, 2018, 08:40:22 pm
Thanks for that Paulca ,
The 1.4 thing is just a rule of thumb ,different factors like load regulation of the transformer  and actual current vs rated current all add variables into the equation . When speccing a transformer for a given job ,you have to not only calculate the output current ,but also add in the ac current handled by the smoothing capacitors too ,typically over speccing your transformer by 50% compared to the load current is a good starting point , as we have seen the power consumption of the FY6600 is about 10 watts max , a 20 watt rated core here will run nice and cool  ,where a lower VA rated component might run hot and because its at the edge of its capabillity magnetic leakage/interference and noise  starts to become a bigger issue also . The great thing about the old style linear supply is that if its nicely over specced for the job you can be sure of a very long and trouble free life , switchers tend to have a limited lifespan ,and once capacitor values stray beyond a certain margin catastrophic failure isnt far off .
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DaveR on February 25, 2018, 09:06:58 pm

I don't order from Mouser, but RS Components or for a sizable order Farnell.  RS have free shipping and no handling charge for any size of order including a single 0.1p resistor technically.  Though you would feel like a bit of a dick doing that to them.


I didn't realise RS had free postage on online orders now, but I've just checked and you're right - although I'm sure when I ordered some stuff from them a few months ago I had to add a load of basket fillers to take the value over £25 to get the free delivery.  I've also just found that they've got a branch nearby, which could be handy.

I was quite interested in Insatman's D75J TCXO from Digikey until I saw the price: £8 for the pinhead sized component (not too bad when you consider what it does), and £12 for the postage!  But I could have it delivered free if I bought another £20+ worth of basket fillers to go with it.  I think I'll just live with the 4ppm error I've got. (And it's stable within 10 minutes.)

Dave
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Chris56000 on February 25, 2018, 09:09:28 pm
Hi!

Trying to find a good economically priced small transformer with two suitable secondaries small enough to go in the FY6600's case is like trying to find a needle in a haystack with eBay's useless search engine, but I located this one - it's a low-profile R-core transformer of 30VA rating, the two 9V secondary windings can be connected in parallel IF you are careful of course to give 9V @ 1.4A. Best of all, it has dual-primary 115/230V for world-wide application plus an inter-winding screen as well!

I've ordered one to try in mine!

https://www.ebay.co.uk/itm/115V-230V-30W-High-Quality-Audio-R-Core-Transformer-15V-15V-9V-9V-For-Preamp/131588122667?hash=item1ea343682b:g:PfgAAOSwBadTpmyy (https://www.ebay.co.uk/itm/115V-230V-30W-High-Quality-Audio-R-Core-Transformer-15V-15V-9V-9V-For-Preamp/131588122667?hash=item1ea343682b:g:PfgAAOSwBadTpmyy)

Opinions please?

Chris Williams

PS!

Suggestion for 5V linear supply to use with above transformer:-

https://www.ebay.co.uk/itm/L7805-Step-Down-7-5V-35V-to-5V-DIY-Kit-Power-Supply-Module-new-UK-seller/271656192244?hash=item3f3ff888f4:g:2lAAAOSw1XdUV6q1 (https://www.ebay.co.uk/itm/L7805-Step-Down-7-5V-35V-to-5V-DIY-Kit-Power-Supply-Module-new-UK-seller/271656192244?hash=item3f3ff888f4:g:2lAAAOSw1XdUV6q1)

Suggestion for ±15V dual linear PSU module for use with above transformer:-

https://www.ebay.co.uk/itm/AC-DC-Voltage-Regulator-LM317-LM337-Adjustable-Filtering-Power-Supply-DIY-Kits/302371834320?hash=item4666c409d0:m:m3whryg5vfLibDo-QTtc79w (https://www.ebay.co.uk/itm/AC-DC-Voltage-Regulator-LM317-LM337-Adjustable-Filtering-Power-Supply-DIY-Kits/302371834320?hash=item4666c409d0:m:m3whryg5vfLibDo-QTtc79w)

NB!

The links I've provided refer to kit items, to facilitate substitution of higher quality electrolytic capacitors in the designs, etc. I believe the maximum current ratings of these kits are suitable for adequately powering the FY6600's electronics, but please feel free to correct me if I'm wrong!

Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DerKammi on February 25, 2018, 09:16:44 pm
Another quick update before going to bed.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DaveR on February 25, 2018, 10:11:17 pm

Trying to find a good economically priced small transformer with two suitable secondaries small enough to go in the FY6600's case is like trying to find a needle in a haystack with eBay's useless search engine, but I located this one - it's a low-profile R-core transformer of 30VA rating, the two 9V secondary windings can be connected in parallel IF you are careful of course to give 9V @ 1.4A. Best of all, it has an inter-winding screen as well!


That's the transformer I used, Chris - it's light, cool and, as far as I can tell, very low noise (as r-cores are supposed to be).  I only used one 9v secondary, which is more than enough for the job, as I thought I'd keep the second one free to drive a fan if it needed it (it doesn't).

The bipolar board is also the one I used; it's got nice big tits smoothing capacitors on it, which is a good thing, and it produces very little heat.  It's bigger than it looks in the picture, but still fits in the case ok.

As you've got an adjustable 12 - 15v supply, and as you can't guarantee that the 5v module will actually deliver 5v, why not allow yourself some leeway and get the LM317 version for a few pence extra, then you can dial in whatever exact voltage you want?  (I set mine to 5.1v to give a little extra headroom for the regulators on the main board to play with).  I didn't use the 5k pot that comes with it,  but mounted a multiturn trimpot on a piece of veroboard and put that in its place.  I also left off the switch, and the big spring connectors (I used a screw connector block instead).

The transformer and modules are all fixed with nylon spacers and screws, and I fitted a switched earth wire to the 0v line on the bipolar board so that the whole thing can be either earthed or floating.

Enjoy yourself putting it all together!

Dave
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Chris56000 on February 25, 2018, 10:40:21 pm
Hi!

Quote
As you've got an adjustable 12 - 15v supply, and as you can't guarantee that the 5v module will actually deliver 5v, why not allow yourself some leeway and get the LM317 version for a few pence extra, then you can dial in whatever exact voltage you want?  (I set mine to 5.1v to give a little extra headroom for the regulators on the main board to play with).  I didn't use the 5k pot that comes with it,  but mounted a multiturn trimpot on a piece of veroboard and put that in its place.  I also left off the switch, and the big spring connectors (I used a screw connector block instead).

Thanks for your tip Dave - I do industrials at work where I routinely have to fit new 7805s and the ones my employer buys are literally pot-luck as to how accurate they are!

As the FY6600 is only known to take 400-500mA @ 5V, me thinks this one is perfect, not needing anything anything omitting, chucking-out or the board altering! I've ordered one!

https://www.ebay.co.uk/itm/LM317-Adjustable-Power-Supply-Board-With-Rectified-AC-DC-Input-DIY-Kit/401482358932?epid=21010444566&hash=item5d7a36a094:g:2NsAAOSwaLdaaDEO (https://www.ebay.co.uk/itm/LM317-Adjustable-Power-Supply-Board-With-Rectified-AC-DC-Input-DIY-Kit/401482358932?epid=21010444566&hash=item5d7a36a094:g:2NsAAOSwaLdaaDEO)

Chris Williams




Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DaveR on February 25, 2018, 11:07:28 pm
That's just the job, Chris.  How have I not come across that one before?  (I've now ordered a couple for the bits box.)

Regards,
Dave
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: soundtec on February 26, 2018, 01:52:45 am
I tried out Fremens tweeked software earlier ,thats really handy that it runs seamlessly with the original , even the small changes to the look of it so far is a big improvement over the original ,the white text on black/grey backround looks great ,and the bigger waveform window helps too .

Tomorrow I might try making a steel screening plate to sheild the main boards from any radiated noise from the psu , I might also ask a friend with serious test gear and sixty years electronics experience to run through the unit and pass on any suggestions he might have for improvements .

Apart from non destructively fitting the other psu I had ,I havent done anything yet that voids my warranty , Id prefer to get a few hours up on it and do proper functional tests before filing and drilling ,just in case it has to go back.
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: DaveR on February 26, 2018, 02:20:00 am
I tried out Fremens tweeked software earlier ,thats really handy that it runs seamlessly with the original , even the small changes to the look of it so far is a big improvement over the original ,the white text on black/grey backround looks great ,and the bigger waveform window helps too .


I agree.  I gave the software a run out as well (Control window, anyway), and it's a big improvement in layout and appearance compared with the original.  All the functions work as they were intended - only the offset display and sliders need more work, but, as fremen said, they aren't a priority at the moment.  Thanks again for what you are doing, fremen67!
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
Post by: Propretor on February 26, 2018, 02:27:50 pm
Hi!
Is there a difference in hardware from the models FeelTech FY6600 60MHz and FY6600 30MHz?
Or the difference is only in FW?
Is there a problem with the FW version? I correctly understood that versions 3.0 and 3.1 are bad, and 2.9 or 3.2 are successful?
Title: Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Genera