JunTek PSG9080 Programmable Signal Generator (80 MHz - 300 MSa/s - 14-bit)

[ptluis]

1) Duty cycle don't works properly for the frequency 1'000'000 Hz and above. If you set 999'999 Hz or below that it works ok. But when you set frequency just 1 Hz above, the duty cycle setting is no more works as expected. This is obviously firmware bug, probably just some kind of mistyping in the source code or something like that. But be aware, with current FPGA firmware 1.20 you will be unable to setup duty cycle for the frequency 1 MHz and above. You can setup duty cycle for higher frequency on the display UI, but the actual signal output will be invalid. It stays close to 50% for any setting from 0 to 99.99%, but it is not exactly 50%, the actual duty cycle changes for about 2-5% instead of 0-100%.

Hello radiolistener, has this problem been solved? I was thinking about buying this generator, but after reading this I suspended my purchase. I usually use square wave above 1 MHZ with variable duty cycle to test some sensors and stuff.

The PC software on the Juntek website is corrupted and has a virus. Is there another site where I can download it? I need the software to create and add other waveforms that don't exist on this device.

I'm using the FY6800 at the moment. In your experience how does the PSG9080 compares to FY6800?

Regards

[radiolistener]

Hello radiolistener, has this problem been solved? I was thinking about buying this generator, but after reading this I suspended my purchase. I usually use square wave above 1 MHZ with variable duty cycle to test some sensors and stuff.

No. It needs to update firmware in order to test if this bug was fixed in a new firmware. But I'm afraid to do it, because it may brick device and I don't have backup file to restore it. One people already reported that he bricked his device with firmware update. Therefore I am afraid to try firmware update without backup file for JTAG programmer.

The PC software on the Juntek website is corrupted and has a virus. Is there another site where I can download it? I need the software to create and add other waveforms that don't exist on this device.

Yes, the virustotal reports a virus for software from official site. But actually it doesn't needs. I tested it in isolated virtual environment (for safety purposes against viruses) and found that official software just allows to control signal generator from PC.

The only feature that is really needed is ability to download and upload arbitrary waveforms.

So, I created a small command line tool which allows to download and upload arbitrary waveform with no needs to install software. It is available on github, include source code:
https://github.com/qrp73/PSG9080_ARB

and works very well. It allows to upload and download waveform in two formats:
- 14-bit format (waveform is uploaded and downloaded from device as is, with no conversion), this is default format for my tool
- 16-bit format (it needs to convert data from 16-bit to 14-bit before upload), this format is used by official software

The conversion 16 to 14 bit which is used in official software may be unwanted if you want better control on precision of the waveform data, because 16 to 14 bit conversion is lossy and you may want to control how this loss should be done. This is why I added support for 16 bit format just for compatibility with files taken from original software. By default my tool works with 14 bit format and upload data into device as is with no conversion, so you can take full control on waveform data. But you can still use 16 bit format files to use waveform files taken from original software. It is possible by using specific command line options.

My tool doesn't have graphical editor, because I'm too lazy to do it. This is just a command line tool, it allows to download arbitrary waveform from PSG9080 into file on your PC or upload arbitrary waveform from file on your PC into PSG9080 and that's it.

The file format is pretty easy, this is just a text file with decimal unsigned values separated by new line separator. It consists of 8192 lines (8192 points) with values from 0 to 16383. You can create such file with MATLAB, R or other software.

You can use this command line tool from windows, linux or mac-os.
For linux and mac-os just install mono package and start the exe file with mono.

I'm using the FY6800 at the moment. In your experience how does the PSG9080 compares to FY6800?

I don't have FY6800, so I cannot compare. At a glance, PSG9080 has more clean and stable waveform, because I was seen worse signal from other users with FY6800.

Also PSG9080 has very nice front panel with large display and nice buttons. So, if your eyes vision is not perfect, it's better to use PSG9080, because it has more large text on display.

[ptluis]

No. It needs to update firmware in order to test if this bug was fixed in a new firmware. But I'm afraid to do it, because it may brick device and I don't have backup file to restore it. One people already reported that he bricked his device with firmware update. Therefore I am afraid to try firmware update without backup file for JTAG programmer.

That's what I was afraid of. So the seller was trying to deceive me when they said "there's no such problem". Unfortunately I can't use this device without a full working duty cycle. It's better then to find other device while still using the fy6800.  Concerning firmware updates I've read your post and the other user that bricked his unit. Both brands have the same problem on their websites, corrupted, non working firmware. This looks like feeltech, their software doesn't work anymore for firmware or software updates because they change the domain name  so no more automatic updates (not even manual). This automatic firmware upgrade is something I'm not really a fan...

Yes, the virustotal reports a virus for software from official site. But actually it doesn't needs. I tested it in isolated virtual environment (for safety purposes against viruses) and found that official software just allows to control signal generator from PC.

The only feature that is really needed is ability to download and upload arbitrary waveforms.

So, I created a small command line tool which allows to download and upload arbitrary waveform with no needs to install software. It is available on github, include source code:
https://github.com/qrp73/PSG9080_ARB

and works very well. It allows to upload and download waveform in two formats:
- 14-bit format (waveform is uploaded and downloaded from device as is, with no conversion), this is default format for my tool
- 16-bit format (it needs to convert data from 16-bit to 14-bit before upload), this format is used by official software

The conversion 16 to 14 bit which is used in official software may be unwanted if you want better control on precision of the waveform data, because 16 to 14 bit conversion is lossy and you may want to control how this loss should be done. This is why I added support for 16 bit format just for compatibility with files taken from original software. By default my tool works with 14 bit format and upload data into device as is with no conversion, so you can take full control on waveform data. But you can still use 16 bit format files to use waveform files taken from original software. It is possible by using specific command line options.

My tool doesn't have graphical editor, because I'm too lazy to do it. This is just a command line tool, it allows to download arbitrary waveform from PSG9080 into file on your PC or upload arbitrary waveform from file on your PC into PSG9080 and that's it.

The file format is pretty easy, this is just a text file with decimal unsigned values separated by new line separator. It consists of 8192 lines (8192 points) with values from 0 to 16383. You can create such file with MATLAB, R or other software.

You can use this command line tool from windows, linux or mac-os.
For linux and mac-os just install mono package and start the exe file with mono.

I manage to get the full working software from tony albus youtube page. I also download your software but can't test it because I didn't purchase this generator  but tell me how do you draw the waveforms?

I don't have FY6800, so I cannot compare. At a glance, PSG9080 has more clean and stable waveform, because I was seen worse signal from other users with FY6800.

Also PSG9080 has very nice front panel with large display and nice buttons. So, if your eyes vision is not perfect, it's better to use PSG9080, because it has more large text on display.

Correct PSG9080 it's better than fy6800 cleaner waveform from what I saw in video reviews, apart from jitter, amplitude stability and wave distortion was solved by using a linear power supply made from a old transformer and some 7812, 7912 and 7805 linear regulators.


I find out who manufactures PG9080, Hangzhou Junce Instruments Co., and did you know they are releasing a new brand name for their FG? ready? JunCtek    This chinese guys don't realise what words can do to a product 

[radiolistener]

That's what I was afraid of. So the seller was trying to deceive me when they said "there's no such problem".

The seller may be right. I got my device about year ago, so a new device may come with the more fresh firmware and it is possible that this bug is already fixed. I don't know.

but tell me how do you draw the waveforms?

I don't paint it, because it is not precise method. I just write my own code to generate it from a function or script. The same you can use MATLAB, R, python or other language to do that. You can also plot the waveform from a file in such way.

[ptluis]

I don't paint it, because it is not precise method. I just write my own code to generate it from a function or script. The same you can use MATLAB, R, python or other language to do that. You can also plot the waveform from a file in such way.

thank you for the info 

[Neper]

Correct PSG9080 it's better than fy6800 cleaner waveform from what I saw in video reviews, apart from jitter, amplitude stability and wave distortion was solved by using a linear power supply made from a old transformer and some 7812, 7912 and 7805 linear regulators.

I'm running my 9080 with an external linear PSU connected to the 5 V DC input. Its built-in PSU injects far too much noise back into the mains.

I find out who manufactures PG9080, Hangzhou Junce Instruments Co., and did you know they are releasing a new brand name for their FG? ready? JunCtek    This chinese guys don't realise what words can do to a product 

My favourite is still Rigol. Supposedly from the French 'rigoler' or 'rigolo'.

[radiolistener]

I'm running my 9080 with an external linear PSU connected to the 5 V DC input. Its built-in PSU injects far too much noise back into the mains.

I power it from a USB 10000 mAh power bank. But it consume high current, about 0.9-1.5 Amps, it depends on selected mode and selected amplitude, so it needs good thick power cable. With cheap Chinese thin cables voltage drop is too high and you can see that display is dimmed.

Interesting, does someone tried to install bipolar linear power supply for output driver to disable it's onboard DC/DC converters?

[ledtester]

FWIW, a video by Jerry Walker comparing the harmonics and noise floor of a couple of different signal generators including the PSG9080, a SDG1020, TTi  TGR1040 and Rhode and Schwarz SMIQ 02B.

Juntek PSG9080 Harmonics Comparison -- Jerry Walker
https://youtu.be/Vq6sbQ_OCAs

[fjalvingh]

Just for posterity: I finally managed to resurrect my bricked Juntek PSG9080, as follows:

* Switch off AC power at the back
* Keep the 8 on the keypad pressed then switch on AC power, keep 8 presse
* Keep 8 pressed and press the ON button
* Release the 8.

This should now show a bootloader on the screen. Connect to USB, press 1, and update with the files attached to this message and the Juntek upgrade tool. You need to run both files: one is for the MCU, the other for the FPGA.

Thanks a lot to this post for the method to access the bootloader > https://www.eevblog.com/forum/testgear/joy-it-psg-9080-firmware-failure/msg4559212/#msg4559212

[torch]

In case  it's of interest to readers: 

There's a Koolertron CJDS98 which appears to be the same as this Juntek 9080.

If you download the zip file software and docs package pointed to by the Koolertron vendor on amazon.com, it contains a manual titled PSG9080, and showing a picture of the Juntek.

Of course "same" is relative, as there could well be hardware and firmware variations.

There is a separate, Koolertron branded, manual. It's hosted on the same IP address as the Juntek manual. The manuals are virtually identical inside.

[Quarlo Klobrigney]

The first time I used the generator, the power supply splattered the entire MW and SW bands (don't even ask about LW) on a radio I was tying to align.


I bought it to align the big stuff (you Europeans know the type) from the 50's and 60's as it was smaller than my FY6900 that's wedged in between other pieces of equipment on the overhead bench.


That power supply is absolute trash, How do they justify selling the generator for such a price with that thing powering it.
I set it aside to put a linear supply to it at a later date. 2 years later it still awaits.....


Quote from: Neper on 2021-10-16, 10:27:49

>Quote from: ptluis on 2021-10-14, 06:38:23

Correct PSG9080 it's better than fy6800 cleaner waveform from what I saw in video reviews, apart from jitter, amplitude stability and wave distortion was solved by using a linear power supply made from a old transformer and some 7812, 7912 and 7805 linear regulators.

I'm running my 9080 with an external linear PSU connected to the 5 V DC input. Its built-in PSU injects far too much noise back into the mains.

[kosmos]

what do you think is the Joy-it PSG9080 or the JUNTEK part newer or preferable. I ordered the Joy-IT PSG9080, maybe I'll get a RIGOL DG10xxZ for comparison.

[Bravo]

I found that Norton antivirus corrupted the PC software. When I used a laptop which does not have Norton on it there was no problem.

[Edison]

The source in the PSG9080 doesn't just make a mess of the network and the output, I hear quite high tones and I can't sit near it when it's on, I normally hear a whistle from the transformer - for now, operation at 5V - I plan (two years) to convert it to a linear source and finish the input for EXT 50MHz

Just an addition: the power supply beeps audibly only without load, yesterday I thought of trying to see what the small plate can withstand - the power supply shut down at 4.3A and supplied 3A without a significant increase in temperature

[radiolistener]

yes, mains PSU module used in this signal generator has issues. It has audible noise and may inject some noise interference into mains. I recommend to replace it with something better quality PSU module or just power it from external 5V / 2A PSU. You can power it from USB power bank.

[Muxr]

I don't have a sig-gen that can produce such high frequency (other than my RF signal generators). Was interested but part numbers being lasered off is a big turn off for me. How far we've come.

We went from quality equipment and companies which would provide beautiful service manuals with schematics and even provide you with a roll of factory solder to companies lasering off, off the shelf component part numbers. Such a shame.

[Edison]

module or just power it from external 5V / 2A PSU. You can power it from USB power bank.

Attention! the minimum requirement for a DC power supply is 3A, during normal operation it can easily reach 1.8A under load, and at the moment when another command comes, it will easily exceed the limit of two Amps and distortion may occur due to insufficient power supply. As I already wrote, the original source can handle 4A without a problem.

Nice day 🙂 Tom

[Edison]

So I did a little research, an audio quality Ultra Low Noise linear power supply will easily swing over $100 (think with professional grade mechanical modifications). It is a question of whether this investment is worth it and whether an ordinary linear source with slightly better filtering will suffice.

First I'll do another measurement to see how much noise from the source affects the generator board, from what I've found so far the main board itself is producing some noise.
Thanks to the oscillator's fine correction function, the effect of the external reference is not satisfactory as Tony Albus found out while editing

[Edison]

I almost forgot: I have the GOUPCHN logo on the device, but inside it says Juntek - HW says 1.2 and the board says 1.3

[RUS]

Hi All

Has anyone tested sweep frequency on VCO mode ( to connect sawtooth to MOD input  5v p/p offset 2.5 v)?  It works?

[radiolistener]

So I did a little research, an audio quality Ultra Low Noise linear power supply will easily swing over $100 (think with professional grade mechanical modifications). It is a question of whether this investment is worth it and whether an ordinary linear source with slightly better filtering will suffice.

I think there is no sense to use 100 USD power supply here. You can use cheap but good quality power supply.

Note that there is DC/DC step-up converter to get bipolar power for output amplifiers. If you want to get the best quality signal, there is a sense to disable onboard DC/DC and replace it with external bipolar linear PSU. I believe such mod can give you the best signal that can be achieved on such kind of type signal generator.Also it should fix clipping issue which happens sometimes at 25 Vpk output with 50Ω load.

[Edison]

Note that there is DC/DC step-up converter to get bipolar power for output amplifiers.

The switching power supply replacement project was suspended for this reason. The DC/DC converter will likely be retained for the 5V external power option, but the power supply will be reworked to be linear when powered from the mains.

[eTobey]

How does this look to you?

[Kean]

How does this look to you?

I added a plastic washer under that screw on mine.

[eTobey]

How does this look to you?

I added a plastic washer under that screw on mine.

Allthough it does not answer my question, it is still a good suggestion. 

To me it looks like "Guys... we fucked up. How can we fix it? ... we are lucky, there are no traces, and we can just drill a hole."

How are these BNC sockets held in place? Just by those connections?

I was just about to order this product, when i saw this. Now i ordered a Rigol for the same price.