i see tea'ism comes to the party now, after siglenism... find Dave's video in the early age... DSO is not for Vdc accuracy... why this has to happen so many times? why?
The selling point of 12bit DSOs is that they're more accurate than 8 bit DSOs. IIRC, Rigol marketing said 60%. So, it seemed to me that testing the accuracy would be interesting. I sought to determine if the DSO was truly accurate or just had improved dynamic range.
Gave a quick look at our clients 824 (we haven't delivered yet, as client is tied up) using our in-house derived squarewave generator (precision duty-cycle and amplitude squarewave derived from precision 5 volt reference).
https://www.eevblog.com/forum/testgear/ac-rms-dmm-tests/msg3940957/#msg3940957Results were very good wrt using a precision squarewave from above at 250Hz. Reference source confirmed with our latest KS34465A (we have 3) and our DMM6500. We periodically use this reference source to quickly check each DMM (also SDM3065X, HP34401A, AG34401A) to make sure that one isn't issuing
rouge rogue readings.
DHO824 measured with 1000 averages.
Vavg = 2.5001VDC
Vrms = 2.5092Vrms
BTW why is this important for us? We often employ a DSO to view & measure complex waveforms and often these waveforms are beyond the frequency range where one would expect the DMMs to render a decent measurement, so we employ the built-in DSO measurements. This all boils down to KTI (Know Thy Instruments) and where and how to apply such. For our work having measurements, statistics and such that "One Can Rely On" is a great asset these modern DSOs possess, same goes for the FFT and Bode Functions
Stated before these are complex data acquisition systems, disguised as scopes, that can do so much more within the hands of experienced users
Side Note: When we acquired our 1st DSO here at the Labs a few years back, it was a Siglent. One of the first things we did was evaluate the measurement capabilities, and how they behaved. Needless to say we were impressed then as we are now with the Rigol DHO824 measurement capabilities, altho the FFT needs some polish, however our client isn't interested in the FFT (nor Bode Function) so for us a moot point in that respect.
Best,