PMT

Photomultiplier/LED box

The photon counting detector, a Photomultiplier Tube (PMT), is mounted in a box and can be illuminated by a red LED (Light Emitting Diodes). Turn the knob labeled "LED" clockwise to increase the LED light level.

Power = +12 V

Pulse Amplifier
The small blue box amplifies pulses from the anode of the photomultiplier before they are fed to the discriminator.

Pulsed LED (not currently connected)
Connect  a TTL (5 volt) pulse to the BNC connector on the back of the demo unit to adjust the second LED inside the box.  The level of the pulsed-LED is controlled by the knob labeled "PULSED LED LEVEL"

Caution
Before opening this box put, disconnect the power.

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