PMT

PMT = Photo Multiplier Tube.

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Tests Performed to Ensure High Speed Amp Function

If the function of the High Speed Amp is in question it can be tested using an oscilloscope. Monitor test point TP4 on the high speed amp board, and then pins 1,2,3,4, and 12,13,14, 15 of the IC, SN75114N. Each should produce a clean square wave, the frequency of which should vary with light intensity