Performa01
I'm not impressed by the HF response step size the first 15ns; there is much undefined over and undershoot. The same behavior can also be seen on the SDS1000HD. Almost as if they use the same front-end design.
Can you also make a test on a 100Hz square wave input signal ? Some recent Siglent scopes also have problems with this (not showing a real square)
Thank you
Why would they not share input design, when their specifications for inputs are pretty much the same...? Of course, they would only share 1MΩ input path design.
Are you referring to images with top part of signal zoomed in 20X ?
(Which by the way is something not many scopes can do, not to mention in this class.)
Your definition of recent is very different from mine. Problems with compensation were in scopes from 2017.. that is going on to 7 years now... there were 3 generations of new products released. Just saying...
Picture SDS824X_HD_PR_1GSa is NOT zoomed in, and clearly shows strange strange aberrations, almost there is a reflected wave interfering with one of the internals...
A TDR or VNA would shed some light on this to see what is going on. (at least on a SDS1000X HD this is possible, but outside the scope of this thread)
There is nothing wrong with sharing a good design, I did not imply this is a bad thing, just an observation, so no defense from your side is needed here.
As for the LF compensation in the front-end, Siglent does not have a good track record for this, specially on the low end scopes. I consider the SDS800 as a low end scope give the fact it has only a 7'' screen hence my curiosity for the LF distortion on this model.
Thanks Performa01 and RF-loop for the tests