Rigol DS1052 AC voltage accuracy

[Oscar]

Hello,

What is the Rigol DS1052 accuracy of the VRMS measurement of an AC wave? Its specifications only cover the DC measurement accuracy.

[tom66]

I would think it would vary with the particular waveform.

[Psi]

dunno about Vrms but I've noticed the measurement resolution in general isn't very good.

Vertical resolution is from 8bit ADC so if your scope is on 5V per div and the signal is only 5V high (1div) that's 255/8 =  0->31 range per div  5V/32 = 156mV steps
Where as if the 5v signal is using all 8 divs its 5v/256 = 20mV steps

If they're using screen data instead of raw ADC its a bit worse, as there are only 234 lines on the screen

This thread talks about the 8bit issue with scopes https://www.eevblog.com/forum/general-chat/rigol-ds1052e-inaccurate-voltage-readings/

[Oscar]

Thankyou for the replies 

[alm]

AC voltage accuracy will depend on the frequency. You can find some frequency response plots for oscilloscopes, this should give you an idea of the error. For most low-end scopes, the error at the rated bandwidth should be about 30%. So for a 100 MHz scope, the amplitude of a 100 MHz sine will be 30% low. Best case (possibly low frequencies) may be equal to the DC spec, worst case will be 30% off. That's why there's no single AC voltage spec in the manual.

Any quantization error will be in addition to the error induced by frequency response.