FeelTech FY3224S 24MHz 2-Channel DDS AW Function Signal Generator

[jcrubin]

Movie of the HP331A repair along with a FY3200s harmonic distortion shootout

[jcrubin]

Showing FY3200 harmonics under magnification

[jcrubin]

Now moving on to sine wave purity/distortion.  Attached is an FFT spectrum of a 10 Vpp set point amplitude at 100 kHz.  Measured fundamental amplitude is +4.8 dB or 1.75 Vrms or 4.94 Vpp (low by 1.2%).  The largest harmonic was the fifth at -51 dB relative to the fundamental.  Based on this spectrum I would say THD is < 0.5% although I don't have a direct THD measurement.  Easily below the published spec of 0.8% at 1 kHz.  See attached scope shot "FY3206S MDO3104 100kHz Sine Spectrum 5Vpp.png".   

Lastly, I checked the noise and distortion while outputting the smallest amplitude set point of 10 mVpp.  The noise on the waveform with the scope set to 1 mV/div was a fuzzy width of the sine waveform of about 0.4 mVp-p or about 0.15 mVrms which is close to the scope's measurement noise.  Looking at the spectrum the largest harmonic is about 40 dB down.  Note that at this small level there are harmonic lines showing up at 140 kHz which is not related to the 100 kHz sine and is either a generator noise and/a very high frequency signal aliasing on the scope's 100 MS/s setting for this measurement.  At any event that spectrum peak is only 30 uV rms.  All in all, pretty good low amplitude results.  See attached scope shot "FY3206S MDO3104 100kHz Sine Spectrum 5mVpp.png".   

Further work on my 331A as well as using a scope of the output to tune in the absolute lowest distortion

Input voltage 5.5VRMS except for 40hz and below    (around 3.7VRMS MAX)  NO LOAD

I REPEAT   NO LOAD MEASUREMENT!!!!

10        .205
20        .195
30        .205
40        .205
50        .195
60        .205
70        .205
80        .205
90        .205
100      .21
200      .21
300      .21
400      .205
500      .21
600      .21
700      .208
800      .208
900      .208
1000    .205
2000    .195
3000    .195
4000    .192
5000    .192
6000    .2
7000    .2
8000    .2
9000    .198
10000  .2
15000  .198
20000  .192
25000  .192
30000  .192
35000  .183
40000  .182
45000  .180
50000  .176

[Wirehead]

What happens at 600 Ohm termination with the distortion levels?  Can you give some at 50 Ohm as well? It would be nice to see

[jcrubin]

Before I give the measurements, you can see the weakness of this unit under load.

Consider 1KHZ  0 OHMS  @ 5.5VRMS = .205

@50 OHMS :

1V RMS =     .175 %
2V RMS =     .900 %
3V RMS =   8.800 %    (clearly visible rounded peaks on the oscilloscope)


I settled on 1V RMS to do the testing.   


                           1V RMS
               0 OHMS            50 OHMS
50            .190                 .215
100          .165                 .172
500          .180                 .180
1000        .170                 .175
5000        .164                 .165
10000      .162                 .175
30000      .156                 .167
50000      .140                 .155
100000    .142                 .155
200000    .130                 .135
300000    .110                 .125
600000    .095                 .110      (MAXIMUM INPUT FREQUENCY) 

Also, a video of the process


 

[venoft]

Does anyone know how to change the input power to 230V? I got mine with a US plug, so it's probably set to 110V.

The inside seems to have a 4-pin power selector (labelled as CN1 and CN2), but without instructions I don't know which combination to use.

Edit: It does seem to work for both 110V and 230V. I removed the circuit board and the power selector only had 1 viable option. So I fired it up and luckaly it didn't explode in my face.

But now I seem to have another issue. When I connect it to my scope, the output voltage (when it's off!) is almost 300V! At 50Hz. It's probably floating, but does anyone has a tip to ground it? Until than I can't use it for anything without frying my circuits.

Edit2: I fixed it. See my other post. https://www.eevblog.com/forum/beginners/function-generator-output-floating-300v!/

[mstck]

I  recently received my FY3224S and I installed the driver and software on my W7 64bit machine. Everything appears to work but the interface is in Chinese. How do I go about changing this to English? I tried downloading the earlier versions of the software in this thread but the same thing happens.

Any help would be appreciated.

[SteveLy]

I  recently received my FY3224S and I installed the driver and software on my W7 64bit machine. Everything appears to work but the interface is in Chinese. How do I go about changing this to English? I tried downloading the earlier versions of the software in this thread but the same thing happens.

Any help would be appreciated.

The link fc12 posted has the English version of the software. Only the earlier version (v1.4 IIRC) is in English. The latest version is Chinese only.

[mstck]

I  recently received my FY3224S and I installed the driver and software on my W7 64bit machine. Everything appears to work but the interface is in Chinese. How do I go about changing this to English? I tried downloading the earlier versions of the software in this thread but the same thing happens.

Any help would be appreciated.

The link fc12 posted has the English version of the software. Only the earlier version (v1.4 IIRC) is in English. The latest version is Chinese only.

Thanks for help.

[rich]

I'm thinking of buying a FT3224S for a project - does anyone know the frequency accuracy in ppm or whether the input can be driven from a 10MHz reference standard to improve overall accuracy?

[pedorie]

Hi,
I also got one. Feeltech FY2200S (10MHz)
but i have a problem with the offset voltage. See measurements below. Can someone please check if they have the same offset issue?

Set      Measured
0.0       0.001
0.1       0.209
0.2       0.314
-0.1      0.045   (positive?  must be negative)
-0.2      -0.059

By the way, the signals are made with 8 datalines from a FPGA (altera max II) these digital lines are fed to a R2R network..

There are some adjustment potmeters inside. found the ofset one and the anplitude one. but there is one more..

Thanks,
peter.

[Stupid Beard]

I'm thinking of buying a FT3224S for a project - does anyone know the frequency accuracy in ppm or whether the input can be driven from a 10MHz reference standard to improve overall accuracy?

There's no external reference input. I don't remember the specs offhand, but I'd say that if accuracy is important then you're best off with a proper function generator. This fills a niche when you don't want to do without and can't justify the cost of something better, but don't mistake it for something more than that.

[nctnico]

I'm thinking of buying a FT3224S for a project - does anyone know the frequency accuracy in ppm or whether the input can be driven from a 10MHz reference standard to improve overall accuracy?

Perhaps you can hack it and change the crystal/oscillator with a more stable one. The generators are certainly cheap enough to take a chance.

[Stupid Beard]

I'm thinking of buying a FT3224S for a project - does anyone know the frequency accuracy in ppm or whether the input can be driven from a 10MHz reference standard to improve overall accuracy?

Perhaps you can hack it and change the crystal/oscillator with a more stable one. The generators are certainly cheap enough to take a chance.

Plenty of room in them, too.

[cdev]

I am basically a Linux user and I don't like to buy hardware that can't work with Linux. But I really need a waveform generator and the price on this one is attractive. Does the included software run under Wine?

What functionality does the software add?

[rich]

There's no external reference input.

Thanks for the clarification. I didn't expect great accuracy so if it accepted a reference then it would have worked for my current project.

Perhaps you can hack it and change the crystal/oscillator with a more stable one. The generators are certainly cheap enough to take a chance.

That is a good thought and I like the spirit however if it isn't successful then it is £60 I won't have to put towards a better function generator. It's a tough decision, I'm going to think it over a bit more.

[Stupid Beard]

I am basically a Linux user and I don't like to buy hardware that can't work with Linux. But I really need a waveform generator and the price on this one is attractive. Does the included software run under Wine?

What functionality does the software add?

It uses a USB to serial converter which Linux picks up just fine. The protocol is documented somewhere earlier in this thread. I started hacking up a Python lib for it, and got most of the way there but didn't get around to finishing it off because I've not needed it in a while. It would be pretty easy to hack up a GUI for Linux but I don't think one exists yet.

The included software is kinda shitty so I never bothered trying it.

[FlyingHacker]

I was surprised at how accurate the frequency my 24MHz Feeltech unit was. All my frequency counters have it dead accurate.

A piece of Tek or HP piece of test gear it is not, but the thing is very effective, and quite accurate, especially for the price.

[rich]

That's good to know. And even if was slightly off then still really good value for money. I've decided to save up a bit longer and find something more fitting to my current needs - I suspect I'll defect to the SDG2042X camp, but will end up with a feeltech in the travel bag eventually.

[jwm_]

So there is a lot of free space in this waveform generator, has anyone attempted a battery conversion yet?

The front board is supplied with a handful of voltages, so would need to generate those from a battery, but seems like it should be doable.

[ferdiii]

Hi guys,
I am having a problem with this device.  I have  installed the driver and software on my W7 64bit machine, but when I connect the fy3224s to the laptop, the program FY3200 PC control software does not recognice the device.
How many programs  have i to install on the laptop?   The Ch340driver,...it is necessary to install on the laptop?


Any help would be appreciated.

[cdev]

Not being a windows guy I don't know what you need to see there but you should look at the device manager to see if whatever (USB to serial, maybe) device they use is listed there. If it isn't maybe you need to install its driver, whatever it is?

[swgertsch]

Hi guys,
I am having a problem with this device.  I have  installed the driver and software on my W7 64bit machine, but when I connect the fy3224s to the laptop, the program FY3200 PC control software does not recognice the device.
How many programs  have i to install on the laptop?   The Ch340driver,...it is necessary to install on the laptop?


Any help would be appreciated.

The way to have described the problem implies that you have two computers you are trying to use the FY3224S device with: a W7 64bit machine and a separate laptop. Your last sentence "The Ch340driver,...it is necessary to install on the laptop?" gives me the impression that you have not installed the required driver on the laptop, only the W7 64bit machine.

Follow the manufacturer's instructions, disconnect the FY3224S, install the supplied (required) USB driver on the laptop and then connect the FY3224S. Worked seamlessly for me.

 

[nctnico]

Is the software any good? The screen looks decent enough.

[swgertsch]

"good" is a subjective term. I would say it is superior to the Chinese version of some software that many FY3200S users initially received, but in reality it is far from complete. It is more like alpha software thrown together for a targeted user base to provide feedback to its developers.

I have been experimenting directly with the device sending commands via a terminal program in order to better understand how to control the device and what can and cannot be done via the front panel and the USB interface. I am using information gleaned from this post and several other sources. I am discovering all sorts of interesting behaviors.  For example:

1) Is is not possible to set the phase angle of the CH1 waveform via the USB interface, but it can be done set though the UBS interface.
2) The internal counter rolls over at  268,435,456 (2**28-1).
3) ... the list goes on.

Right now I am trying to understand the trigger options. I am stumbling around trying to understand what these options do and how to to use them. I would appreciate if someone could provide some clarity. What is the relationship between the counter and the triggering options?