UNI-T UTG932/UTG962 200MSa/s Function Arbitrary Waveform Generator

[valcher]

I would like to clarify what the FPGA firmware is responsible for, the control interface?

[Yuriy V.]

Синтезатор (synthesizer)

[onx]

This firmware UTG900E.bin doesn't have SRC check
We can change FW version to any we want.
Now my 3.06 changed to 1.09

[RogerG]

Hello,

I have a noob question about the UTG 932's frequency jitter. I hope I find a correct description of the effect because I'm no native english speaker.

Since a few days I have a much better 12bit scope here and I'm fiddling around with it and my UTG 932. Above 1MHz sine coming out of the UTG I see an increasing frequency jitter (?) that leads to blurry waveforms. At the trigger point the plotted waveform line is super fine (no wonder) but it becomes more and more blurry if I scroll away from the trigger point and it maxes out 700ns away from trigger point. At 1.4µs from trigger point the wave is perfect thin again and so on.

The measured amount of frequency jitter reaches up to 3ns at a 30MHz sine wave. Is this jitter behaviour of the UTG 932 still normal? Or is my UTG defect? My old scope is still sold, so I can't compare the measurements anymore.

I've tried 50Ohm termination or not. I used different power supplies, BNC cables, scope channels, both UTG 932 outputs. All this with absolutely no effect to the frequency jitter.

Thx for your comments!

Regards
Roger

[RogerG]

A picture always says much more than words, so please find the attached screenshot of a 30MHz sine wave fed from the UTG 932-into my scope. And another screenshot of a 16MHz sine wave.

Is this normal behaviour of the UTG in this use case??

Another interesting point is a FFT view of a 16MHz sine (in the right window) out of the UTG-932 with many transients in a distance of 700kHz and just 21dB lower than the main wave. Same question... normal or not ?? Is my copy bad?

[Aldo22]

normal or not ?? Is my copy bad?

I don't know enough about it and I don't have such a device, but why don't you compare the information in the data sheet with your measurements?
Like "phase noise" and "shake": https://www.batronix.com/files/Uni-Trend/UTG900E/UTG900Edatasheet.pdf

[RogerG]

Hi,

because there is no value for shake at sine waves. And because I don't understand what a value of -125dBc/Hz means at phase noise.

[Aldo22]

Hi,

because there is no value for shake at sine waves. And because I don't understand what a value of -125dBc/Hz means at phase noise.

I understand that you would prefer it if someone with an UTG932 could confirm your measurements.
I can't, but I think that some jitter is normal. It's still a cheap FG.

If you want to know more about it theoretically:
German: https://de.wikipedia.org/wiki/Phasenrauschen#Messung

Lots of background (English)
https://www.npl.co.uk/special-pages/guides/gpg68_noise

Maybe you could ask the question more generally in another subforum. Maybe "Metrology" or "Beginners", I don't know.
There are already such topics: https://www.eevblog.com/forum/metrology/phase-noise-measurement/msg3337416/#msg3337416

[RogerG]

There are so many UTG owners in this thread, and some of them have made detailed analysis of the device.

I was hoping some of the owners could show a fft spectrum analysis of his copy at 30MHz 1Vpp sinusoidal wave...

Thx in advance.

[valcher]

I seem to have found what the write error problem is, the new UTG900 has w25q64 memory, and the old w25q80 memory. And also, there is a slight difference - see the photo.
Now I can't confirm my guess yet, because there is no such memory, but I ordered it and am waiting for it.

[Yuriy V.]

And also, there is a slight difference - see the photo.

Are the FPGA chips used in them completely identical?

[valcher]

All chips are identical, only the FPGA itself is from different manufacturers.
My guess was not crowned with success, I tried to flash a new flash with a programmer, but it did not bring any effect. Moreover, I accidentally rewrote the native flash image and now I can’t revive the generator. If anyone can share the image.