ADC-200/50. Works correctly up to 100 ms timebase

When signals are analysed using a time base =< 100 msec, everything is fine.

when the same signal is analysed using a timebase > 100 msec the shape of the signal is corrupted.

Eg a sinewave is shown as such at time base =< 100 msec, but the same sinewave is shown as .... anything with varying amplitude and shape.

Emilio,

Use Block Mode at the longer time bases. The capture is probably distorting due to a lack of sample rate from the switch to streaming mode at >100ms/div. Using block mode collects the data at full speed into the internal buffer and then transfers it to the PC in blocks. This allows the scope to maintain sample rates at the longer time bases.

This is found in Settings/Options/Advanced.