AN AMPLITUDE DISCRIMINATOR FOR A COUNTING PHOTOMULTIPLIER

An amplitude discriminator is described for a single-electron photomultiplier. It is designed to utilize the peculiarities of the pulse shape at the output of the photomultiplier and the properties of the detected optical signals. It has the following characteristics: input resistance 3-10 OMEGA; conversion coefficient greater-than-or-equal-to 12 m V/muA; passband 100 Hz-30 MHz; instability of threshold discrimination for temperatures ranging from -20 to +40-degrees-C for 8 h of operation less-than-or-equal-to 3 mV; threshold voltage variation 20-1000 m V; minimum discrimination threshold, for which the circuit remains stable, 20 mV; output pulse duration 10 nsec; ECL output standard; positive and negative polarities.