Author Topic: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator  (Read 316062 times)

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Offline plb

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Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
« Reply #450 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.
There is no technical fault too difficult to solve by sufficient application of marketing.
 

Offline DC1MC

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Offline Ebel0410

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Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
« Reply #452 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  ;)
 

Offline Ebel0410

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Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
« Reply #453 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
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)
« Last Edit: January 03, 2018, 11:58:32 pm by Ebel0410 »
 

Offline DaveR

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Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
« Reply #454 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
 
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Offline Chris56000

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Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
« Reply #455 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
« Last Edit: January 06, 2018, 01:18:11 am by Chris56000 »
It's an enigma that's what it is!! This thing's not fixed because it doesn't want to be fixed!!
 

Offline DC1MC

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Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
« Reply #456 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:
 
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Offline Studio1@29

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Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
« Reply #457 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
 

Offline rhb

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Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
« Reply #458 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?
 

Online Marco

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Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
« Reply #459 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.
 

Offline cybermaus

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Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
« Reply #460 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
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 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.




 

Offline cybermaus

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Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
« Reply #461 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

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.

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.





 

Offline Chris56000

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Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
« Reply #462 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
It's an enigma that's what it is!! This thing's not fixed because it doesn't want to be fixed!!
 

Offline DC1MC

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Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
« Reply #463 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
 
 

Offline Chris56000

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Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
« Reply #464 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
« Last Edit: January 10, 2018, 04:17:41 pm by Chris56000 »
It's an enigma that's what it is!! This thing's not fixed because it doesn't want to be fixed!!
 

Offline DC1MC

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Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
« Reply #465 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


 

Offline DaveR

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Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
« Reply #466 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
 

Offline Vytautas

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Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
« Reply #467 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!
 

Offline cybermaus

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Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
« Reply #468 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. 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)

 

Offline Mr. Scram

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Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
« Reply #469 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?
 

Offline Vytautas

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Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
« Reply #470 on: January 11, 2018, 07:58:46 pm »
Thanks, cybermaus, looks to be just it. Well, you get what you pay for.  :(
« Last Edit: January 11, 2018, 08:01:22 pm by Vytautas »
 

Offline cybermaus

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Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
« Reply #471 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.
 
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Online Marco

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Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
« Reply #472 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.
« Last Edit: January 11, 2018, 09:12:05 pm by Marco »
 

Offline rhb

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Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
« Reply #473 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.
 

Offline cybermaus

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Re: FeelTech FY6600 60MHz 2-Ch VCO Function Arbitrary Waveform Signal Generator
« Reply #474 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.
 


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