Collaborators,

Attached is a phone photo of example signals from the new preamps with 3 3He tubes connected to a scope. Scope channels 1,2,3 (color y,c,m respectively) are preamp channels 1,2,3 while 4 (green) is open. Trigger is on channel 3, at 500mV/div and other channels are at 500,200,and 20 mV/Div for channels 2,1,4 respectively. Time scale, though glared out should be 10us per div ( although we saw longer rise times as well). 

Signals were all good for all channels. Coincident with real signals were other negative signals ~15x (750mV/50mV magenta/green) smaller and with a different shape. No positive signals were observed in any channel. 

This picture is representative of the