GBS Elektronik MCA-527 How to do an optimum setup - Manual (Page 3)

Preamplifier signal too large, it exceeds the oscilloscope window and therefore the ADC measurement range.
Reduce coarse gain.
If the amplitude seem quite small, increase coarse gain. If the signal exceeds the oscilloscope window, and not
only in exceptional cases, then decrease coarse gain.
If signal amplitude allows it, coarse gain settings of 2 and 5 should be avoided as they are attenuating the signal
in reality. Especially for HPGe the resolution will then be less than optimum.
Special cases:
If no signal can be seen, and the oscilloscope window tells “Waiting for trigger”, then change Trigger mode to
“free run”.
No signal present. Check if high voltage is set (polarity?), HV cable connected, signal cable connected,
preamplifier supply connected. In case of a very insensitive detector, put a source close to it. Check if there are
preamplifier supply currents. Check detector.