Osci CH:A
AWG is generating a sine wave with pk2pk of 200mV, with a offset of 1V
Goal: Measure this signal AC-Coupled
The first shot of the measured signal is not perfectly AC Coupled - but also not perfectly DC Coupled. Looks like some transitional state of the signal.
Picoscope : 5444B
Connect following ports on Picoscope directly:
AWG:GEN <---> Osci CH:A
AWG is generating a sine wave with pk2pk of 200mV, with a offset of 1V
Goal: Measure this signal AC-Coupled
The first shot of the measured signal is not perfectly AC Coupled - but also not perfectly DC Coupled. Looks like some transitional state of the signal.
That would be the expected behaviour as you will have just switched in the DC blocking capacitor, and this will take a short time to charge up to provide the full block at the desired level. The same effect will be seen if you change the DC component during a capture.
For the sequence above i would expect that this switching from DC to AC coupling procedure takes place directly at point 2 (set_channel) giving the DC blocking capacitor time to settle, but the current state looks like if the coupling is switched at point 4 (collect_segment / run_block) which is in my opinion too late.
Note: a delay of 10 seconds does not change anything
The settings will only be written to the device when the RunBlock command is issued, which is why 1 second and 10 second delays show the same response.
The simple work around would be to apply the settings, do a dummy collection, then run the actual collection.