EEVblog Electronics Community Forum
Products => Test Equipment => Topic started by: Tankj on December 12, 2024, 01:48:02 pm
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After a bad experience on buying the SIGLENT SDS2204X-HD, I finally switched to SDS1204X-HD and SDG1022X-PLUS instead.
EDIT: due to the improper vertical scale setting, all tests blew with green FFT trace has introduced the scope's frontend nonlinear distortion.
I redid these tests in subsequent replys, changing to brown FFT trace To distinguish.
Did a quick signal test on the new SDG1022X-PLUS in to SDS1204X-HD,
SDG outputs 0dBm sin wave into scope 50Ω terminal with RF cable (BNC to SMA on SDG side).
FFT are fixed 256kpts, Varying time bases for different frequency resolution. Flat top on most time for best amplitude accuracy.
Testing desk：
[attachimg=1 width=800]
1，Signal Quality Test
1kHz with 50k span
[attachimg=2 width=800]
1kHz with 2k span
[attachimg=3 width=800]
10kHz with 100k span
[attachimg=4 width=800]
10kHz with 5k span
[attachimg=5 width=800]
100kHz with 1M span
[attachimg=6 width=800]
100kHz with 190k span
[attachimg=7 width=800]
100kHz with 10k span
[attachimg=8 width=800]
1MHz with 10M span
[attachimg=9 width=800]
1MHz with 1M span
[attachimg=10 width=800]
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10MHz with 100M span
[attachimg=1 width=800]
10MHz with 1M span
[attachimg=2 width=800]
25MHz with 100M span
[attachimg=3 width=800]
25MHz with 1M span
[attachimg=4 width=800]
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2，Square Wave and Rise Time
In the SDG1000X PLUS datasheet, the rise time is 10-11nS.
1Mhz and 20Mhz Square Wave, 10.3nS rise time
[attachimg=1 width=800]
[attachimg=2 width=800]
When I set a fast rising edge triangle wave, see what happens
[attachimg=3 width=800]
Rise time is 5.38nS!
3, Higher frequency output
As the top model is 60Mhz, I want try some tricks on my 25Mz model see if it can do higher waves, it actually puts 5.38nS rising time right?
I've tried to create a file containing multiple repeated waveforms and output it in True Arb mode. As the True Arb mode is point-to-point output and the maximum sample rate is 250M, there will only have 4.16 points at each wave if I need to output 60Mhz.
It works. But the wave frequency is coupled with sampling rate, NO stable output at most time. It dose stable just on certain specific frequencies.
Next I tried to use DDS mode, the output was still unstable. Given the way DDS works, the waveforms I created before may have too few points. So I created a 256k waveform consisting of 5 repeated sine waves, and then, the magic happened ::)
20Mhz Arb in DDS mode, outputs 100Mhz sine wave! the rise time is just under 3nS!!
[attachimg=4 width=800]
You can see that the 100Mhz sine wave is very clean, even cleaner than the old Rigol DG1022U at 20Mhz I used before.
I also created a 10 repeated sine waves Arb to test higher frequencies, the output rapidly decays right after 105Mhz, which shows the limit of the output stage bandwidth also the 250M DDS generator.
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After a bad experience on buying the SIGLENT SDS2204X-HD
What happened with your SDS2204X HD? Or are you referring to the issue with the firmware update on the Plus model?
Also, is that TH2830 running as a 2832? 😉
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By setting the output frequency in proportion (here is 5X), we can get any output up to 100Mhz through DDS Arb mode.
Here is a 50Mhz sine wave
[attachimg=1 width=800]
4, FFT test above 25Mhz
50Mhz with 100M span
[attachimg=2 width=800]
100Mhz with 500M span
[attachimg=3 width=800]
100Mhz with 1M span
[attachimg=4 width=800]
at 50Mhz, the signal drops to -0.14dBm
at 100Mhz, it drops to about -1.1dBm
This seems perfectly acceptable to me.
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Thanks for your tests, I'll be deciding in a few months which AWG to buy and every additional piece of information is useful.
There's one thing that looks a bit odd, though.
According to the data sheet, the harmonic distortion should be lower than -65 dBc for frequencies less than 10 MHz at 0 dBm over 50 Ω - your test conditions.
[attach=1]
In many of your pictures, I see values for the 2nd harmonic about 20 dB higher than that.
I can expect some non linearity in the scope front end, but less than what I see.
Maybe changing the vertical scale of Channel 1 to a higher value (200 mV/) would help?
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After a bad experience on buying the SIGLENT SDS2204X-HD
What happened with your SDS2204X HD? Or are you referring to the issue with the firmware update on the Plus model?
Also, is that TH2830 running as a 2832? 😉
Hi, I got a old white version of SDS2204X HD when pay for the newer black version.
I returned it without power on. I don't think there will be any problem with the machine itself. SIGLENT build their machine like a tank.
I sold my 2504X+ to get the money for this new 12bit scope ;) I didn't do the firmware upgrade to the TH2830 in the end, it still stays on TH2830 thing.
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After a bad experience on buying the SIGLENT SDS2204X-HD
What happened with your SDS2204X HD? Or are you referring to the issue with the firmware update on the Plus model?
Also, is that TH2830 running as a 2832? 😉
Hi, I got a old white version of SDS2204X HD when pay for the newer black version.
I returned it without power on. I don't think there will be any problem with the machine itself. SIGLENT build their machine like a tank.
I sold my 2504X+ to get the money for this new 12bit scope ;) I didn't do the firmware upgrade to the TH2830 in the end, it still stays on TH2830 thing.
You returned it because of color?
It is exactly the same machine AFAIK....
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Hi, I got a old white version of SDS2204X HD when pay for the newer black version.
I returned it without power on. I don't think there will be any problem with the machine itself. SIGLENT build their machine like a tank.
I sold my 2504X+ to get the money for this new 12bit scope ;)
Oh, gotcha. I have the white one. The only thing that I know of that's better in the black version is the newer/better BNC ports. I also sold my 2504X+ to get my HD model.
I didn't do the firmware upgrade to the TH2830 in the end, it still stays on TH2830 thing.
It's worth it if you ever need the higher frequencies or DC bias. If not, it doesn't make much of a difference if you have one of the newest firmwares where the arbitrary frequency values also work on the 2830.
You returned it because of color?
It is exactly the same machine AFAIK....
The only difference is the BNC ports AFAIK. Most of the white ones have the 3 split with mediocre chamfer. The newest ones/black ones have the 4 split with better chamfer.
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Thanks for your tests, I'll be deciding in a few months which AWG to buy and every additional piece of information is useful.
There's one thing that looks a bit odd, though.
According to the data sheet, the harmonic distortion should be lower than -65 dBc for frequencies less than 10 MHz at 0 dBm over 50 Ω - your test conditions.
(Attachment Link)
In many of your pictures, I see values for the 2nd harmonic about 20 dB higher than that.
I can expect some non linearity in the scope front end, but less than what I see.
Maybe changing the vertical scale of Channel 1 to a higher value (200 mV/) would help?
Yes, you hit the point.
on the datasheet it also mentions Non-harmonic spurious, which is -70dBc under 50MHz. My test results also seem to be a bit higher.
I don't think its due to the non-linearity of the frontend of scope. The scope has a very good test Results.
But I'll test it as you said and see how it goes.
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Thanks for your tests, I'll be deciding in a few months which AWG to buy and every additional piece of information is useful.
There's one thing that looks a bit odd, though.
According to the data sheet, the harmonic distortion should be lower than -65 dBc for frequencies less than 10 MHz at 0 dBm over 50 Ω - your test conditions.
(Attachment Link)
In many of your pictures, I see values for the 2nd harmonic about 20 dB higher than that.
I can expect some non linearity in the scope front end, but less than what I see.
Maybe changing the vertical scale of Channel 1 to a higher value (200 mV/) would help?
Yes, you hit the point.
on the datasheet it also mentions Non-harmonic spurious, which is -70dBc under 50MHz. My test results also seem to be a bit higher.
I don't think its due to the non-linearity of the frontend of scope. The scope has a very good test Results.
But I'll test it as you said and see how it goes.
For least distortion, don't stretch signal across whole vertical, but less.
Experiment where you have least distortion..
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You returned it because of color?
It is exactly the same machine AFAIK....
Part of it :palm:
plus a cheaper price for SDS1204XHD + SDG1022XPLUS, when the seller didn't want to give full refund. maybe business is hard for him
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You returned it because of color?
It is exactly the same machine AFAIK....
Part of it :palm:
plus a cheaper price for SDS1204XHD + SDG1022XPLUS, when the seller didn't want to give full refund. maybe business is hard for him
Fair enough!
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Thanks for your tests, I'll be deciding in a few months which AWG to buy and every additional piece of information is useful.
There's one thing that looks a bit odd, though.
According to the data sheet, the harmonic distortion should be lower than -65 dBc for frequencies less than 10 MHz at 0 dBm over 50 Ω - your test conditions.
(Attachment Link)
In many of your pictures, I see values for the 2nd harmonic about 20 dB higher than that.
I can expect some non linearity in the scope front end, but less than what I see.
Maybe changing the vertical scale of Channel 1 to a higher value (200 mV/) would help?
Did a quick test again, all settings are the same except the vertical scale to 200mV, this time 0.63Vpp on 1.6V full scale.
You are right, the noisy harmonics are gone, all tests met the specified performance. I can get even lower harmonics with 250mV vertical scale after I did the screenshots.
1kHz, all harmonics are under -65dB :-+
[attachimg=1 width=800]
1Mhz, highest harmonics are around -64.5dB
[attachimg=2 width=800]
25Mhz, -55dB 50Mhz harmonic
[attachimg=3 width=800]
1Mhz spurious, under -77dB
[attachimg=4 width=800]
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For least distortion, don't stretch signal across whole vertical, but less.
Experiment where you have least distortion..
Thanks!
I repeat the test, result on previous post. You are definitely right here, the nonlinearity of the scope frontend indeed have a huge impact on this test!
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I didn't do the firmware upgrade to the TH2830 in the end, it still stays on TH2830 thing.
It's worth it if you ever need the higher frequencies or DC bias. If not, it doesn't make much of a difference if you have one of the newest firmwares where the arbitrary frequency values also work on the 2830.
The only difference is the BNC ports AFAIK. Most of the white ones have the 3 split with mediocre chamfer. The newest ones/black ones have the 4 split with better chamfer.
The main consideration that stop me to install the ST firmware is the impact of second-hand value. I'm thinking to sell it(TH2830) for the newer version, or go for a TH2840A something when I have enough money >:D But this don't have much value other than self-satisfaction, most of my work is in the audio range.
Maybe it will has some other HW difference, like the newer CPUs or FPGAs, like the newer SDS1000XHD has (better Zynq processor).
I'd like to see someone has the black version and teardown >:D >:D
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50Mhz harmonics
[attachimg=1 width=800]
100Mhz harmonics
[attachimg=2 width=800]
Much better than the previous tests!
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Nice work, tidy setup. :clap:
Please tell, what's with the white knob on the SDG1022X Plus encoder ?
Easier to see ?
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The main consideration that stop me to install the ST firmware is the impact of second-hand value. I'm thinking to sell it(TH2830) for the newer version, or go for a TH2840A something when I have enough money >:D But this don't have much value other than self-satisfaction, most of my work is in the audio range.
The ST2832 is more valuable than the TH2830. I sold my upgraded TH2830 on eBay (listed as upgraded TH2830 to ST2832), and did just fine. 😉 The buyer was very happy too.
Switching back and forth is easy anyway, if you have a TH2830 firmware to go back to.
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Nice work, tidy setup. :clap:
Please tell, what's with the white knob on the SDG1022X Plus encoder ?
Easier to see ?
Thanks.
yes I found the large knob a bit fiddly to operate when needed to turn it quickly. the little white one is easier to see too.
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The ST2832 is more valuable than the TH2830. I sold my upgraded TH2830 on eBay (listed as upgraded TH2830 to ST2832), and did just fine. 😉 The buyer was very happy too.
Switching back and forth is easy anyway, if you have a TH2830 firmware to go back to.
I don't have the TH version firmware, guys from TH refuse to give me new firmwares :-[ maybe they have some policies on this. If I can't go back, better to leave the choice to the next user ^-^
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For anyone who wants to try it, the 5X and 10X sinewave Arb files are attached!
It should make your signal 5X or 10X faster if your signal generator support that fast of rise time.
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Nice work, tidy setup. :clap:
Please tell, what's with the white knob on the SDG1022X Plus encoder ?
Easier to see ?
Thanks.
yes I found the large knob a bit fiddly to operate when needed to turn it quickly. the little white one is easier to see too.
Hmmm, is using the keypad unsuitable ?
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Hmmm, is using the keypad unsuitable ?
No, The keyboard is good and quite useful, The only complaint for me is that all buttons are a bit heavy, needs more force to press than usual.
IMO, it is more convenient to use the knob when needs to continuously change paras, say frequency and amplitude. also when selecting Arbs or files.
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Did a quick test again, all settings are the same except the vertical scale to 200mV, this time 0.63Vpp on 1.6V full scale.
You are right, the noisy harmonics are gone, all tests met the specified performance. I can get even lower harmonics with 250mV vertical scale after I did the screenshots.
1kHz, all harmonics are under -65dB :-+
1Mhz, highest harmonics are around -64.5dB
25Mhz, -55dB 50Mhz harmonic
1Mhz spurious, under -77dB
Very kind of you!
Thanks a lot - I suspected as much, given my similar results with SDS804 and self built AD9954 based generator, when compared with a TinySA.
I'm not bothered by the slow rise/fall times of the SDG10?2X-plus for square waves, so I might get one in the close future.
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I'm not bothered by the slow rise/fall times of the SDG10?2X-plus for square waves, so I might get one in the close future.
Based on the results of the 100Mhz sine wave, we can expect faster square wave rise time using Arbs, I'll do this later see how it goes.
Fortunately, Siglent does not limit the bandwidth/rise time of the output stage on SDG1000X PLUS, even on the lowest 25Mhz model :popcorn:
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Hmmm, is using the keypad unsuitable ?
No, The keyboard is good and quite useful, The only complaint for me is that all buttons are a bit heavy, needs more force to press than usual.
IMO, it is more convenient to use the knob when needs to continuously change paras, say frequency and amplitude. also when selecting Arbs or files.
Thanks for your feedback.
I had a short play with SDG1062X Plus on a recent HQ visit and I have some SDG1022X Plus coming in a few weeks when I can investigate your feedback more deeply and maybe pass recommendations to HQ.
For now I'll keep using my SDG6022X.....
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Square Arbs.
1Vpp square into 50Ω terminal,
C3 is Ordinary built-in square wave,
C4 is Arb square，
100Hz 11.12ns Vs 5.78ns rise time, more ripple on the faster square wave is expected.
[attachimg=1 width=800]
1Mhz, same result
[attachimg=2 width=800]
10Mhz, very noticeable ripple on faster square wave.
[attachimg=3 width=800]
20Mhz, Arbs are in DDS mode (True Arb can't do it due to the 250M max sample rate)
We get that classic DDS jitter here.
[attachimg=4 width=800]
Any higher square wave above 20Mhz is useless on SDG1000X PLUS as limited high frequency content makes it closer to a distorted sine wave.
If you really needs faster edge, the Arb square wave will simply do some help.
Not as exciting as 100Mhz sine wave though. ::)