Siglent SDS2000X HD, 12bit, 2GSa/s high definition oscilloscope serie.

[KungFuJosh]

with the setting in the tp.png image, you can set the low-pass filter to a minimum of 20 kHz.

Interesting. It seems the crappier you set the Acquire settings, you can also lower the Corner Frequency further.

These are the frequencies Martin mentioned...

[Bad_Driver]

It becomes much easier if you switch „adaptive sample rate“ on. Than the scope choose the sample rate for your filter settings. There is a formula in the manual I will never understand.

Don‘t forget to switch it off after your filtering measurements, this run me crazy with my intermediate 800HD before I recognized it.

[egonotto]

Hello,

thanks, if I want a cut-off frequency of 30 Hz, the sample rate must be between 120 Hz and 3000 Hz.

Best regards
egonotto

[Bad_Driver]

Hello,

thanks, if I want a cut-off frequency of 30 Hz, the sample rate must be between 120 Hz and 3000 Hz.

Best regards
egonotto

Yes, it works. 20 Hz 1Vpp with 500 Hz 0.2 Vpp combined, LPF 30 Hz
see settings

[KungFuJosh]

Yes, it works. 20 Hz 1Vpp with 500 Hz 0.2 Vpp combined, LPF 30 Hz
see settings

It only seems to work if you're using a single math channel. By setting Adapt Sample Rate active using 2 math channels makes it fail:



In reply 1300 with manual settings, I was able to correctly count both frequencies and display them in their awkward glory.

I think setting the Trigger Coupling frequencies arbitrarily is the right way to do this if it will work. I don't see why it shouldn't since the datasheet shows two separate values for them.

[KungFuJosh]

Hmmm. Looks like setting different filter frequencies with each channel works better, but it's still a little odd.

[XYZVector]

So I found some siglent 2104X-HD on aliexpress for the smoking price of 714.00 however I am sketchy that the scope is either a refurb, and has issues. Or it's not really a 2104X-HD and it's a 2104X-U or some trick. Plus ordering something from AliExpress will be hard to return if it isn't as advertised. Any thoughts on this?

[KungFuJosh]

Any thoughts on this?

If it's too good to be true, then it probably is.

Share a link if you want us to look anyway.

[Bad_Driver]

So I found some siglent 2104X-HD on aliexpress for the smoking price of 714.00 however I am sketchy that the scope is either a refurb, and has issues. Or it's not really a 2104X-HD and it's a 2104X-U or some trick. Plus ordering something from AliExpress will be hard to return if it isn't as advertised. Any thoughts on this?

DON‘T DO THAT! I‘m in trouble since I bought a nice CarPlay/DashCam direct from China, realy a nice product (from Aoocci) but the front cam is not working. CarPlay works great. But the mail fee for an exchange is nearly 1/3 of the price.

I think Welectron is also present in USA and they have the 2104HD on stock. And ask for a EEV-Blog discount.

[Martin72]

I think you mean HP to block the low frequency

This would be counterproductive if you want to suppress the 10kHz carrier frequency in order to display the 400Hz sine wave contained in the PWM.

[DaneLaw]

So I found some siglent 2104X-HD on aliexpress for the smoking price of 714.00 however I am sketchy that the scope is either a refurb, and has issues. Or it's not really a 2104X-HD and it's a 2104X-U or some trick. Plus ordering something from AliExpress will be hard to return if it isn't as advertised. Any thoughts on this?

A link would be more helpful.
IF you want users to help and decipher what it is.

[KungFuJosh]

I think you mean HP to block the low frequency

This would be counterproductive if you want to suppress the 10kHz carrier frequency in order to display the 400Hz sine wave contained in the PWM.

Ah, I read it backwards then. I thought you were doing the reverse. You said "filtering out a 400Hz sine wave from a 10kHz PWM" - I thought you were trying to ignore it, not isolate it.

[tautech]

So I found some siglent 2104X-HD on aliexpress for the smoking price of 714.00 however I am sketchy that the scope is either a refurb, and has issues. Or it's not really a 2104X-HD and it's a 2104X-U or some trick. Plus ordering something from AliExpress will be hard to return if it isn't as advertised. Any thoughts on this?

If from Testing Equipment Wolrd Store you need select the model and the low price was not SDS2104X HD.
The link only shows the earlier cream/beige models, not the latest in 12bit dark clothes.

[KungFuJosh]

Oh, that's the typical aliexpress bullshit. You search for something looking for the best price, and you click on it, but instead of it being the thing you wanted, it's showing the price for an accessory most of the time.

The cheap price is for the SDS1072X HD 70MHz, once you choose SDS2104X HD, the price goes to $3200. No thanks.

[KungFuJosh]

I had some weird behavior with Bode plots yesterday. Of course, I can't recreate it today. 🤦

Anyway, I was plotting some guitar pickups using a device called the Integrator made to add a load to simulate a guitar circuit. Both the loaded and unloaded plots had a weird HPF that cut off low frequencies. This happened while using the SDG2122X externally for the Bode plot:



Somebody on the guitar pickup site said:

Somewhere in your test setup there must be an ac coupling with too high low frequency roll off (250-300 Hz).

So I tried with the internal AWG and the plot looked correct:



Today I wanted to see what the problem was, so I switched back to the external AWG, and I can't reproduce the problem. I assume this means there was something else on that caused the issue, but I have no idea what or how. 🤷

Any ideas?

Thanks,
Josh

[mawyatt]

Look at CH1 setting, AC 50Ω and AC 1MΩ.

Also note Full BW and 20MHz BW setting, which shouldn't make much of a difference at 20KHz.

Best

[KungFuJosh]

Look at CH1 setting, AC 50Ω and AC 1MΩ.

Also note Full BW and 20MHz BW setting, which shouldn't make much of a difference at 20KHz.

Thank you, I'll try setting CH1 back to 50Ω and see if that causes the same effect.

I put the 20M filter on later to avoid some noise, but that was unrelated to this. 😉

ETA: Confirmed, Mike wins again. Thanks!

[mawyatt]

Sure hope that pickup doesn't have the low frequency hi-pass characteristic. Wouldn't want to hear Ritchie Blackmore's Highway Star using that pickup

Best,

[KungFuJosh]

Sure hope that pickup doesn't have the low frequency hi-pass characteristic. Wouldn't want to hear Ritchie Blackmore's Highway Star using that pickup

lol, no. The flat response in the low frequencies is the correct plot. The incorrect setting on CH1 actually made the whole thing uglier. The attached comparisons are of the same pickup.

[Grandchuck]

Had a play around with EasyWaveX and found it compatible with the AWG in the SDS2000X HD.  The software is a bit buggy but useful for the price

[Grandchuck]

As posted before, EasyWaveX is a bit buggy.  The first screen shot below shows one example of the equation editor used to produce an AM signal.  Note the number of samples: sometimes this is greyed out? for this particular generator (SAG1021) and sometimes the sample number changes to that shown when the SAG1021 model is selected.  Selecting other AWGs such as the SDG2000 allows larger samples such as 65536.

In any case, it works and is useful.  Screenimg1 below shows an AM signal from the SAG1021 compared to an AM signal produced by a SDG2000.  Screenimg(x) shows that the SDG2000 signal is cleaner.