Ludlum Measurements 12, Technical Manual

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Model 12 Technical Manual
Section 7
Ludlum Measurements, Inc. Page 7-5 July 2017
2. Neutron
3
He detectors typically require a -2 mV threshold and
about 1700 Vdc. Neutron BF
3
detectors typically operate at
1750 Vdc and -30 mV threshold.
3. Gas proportional detectors need P-10 gas, so check the window
for tears or leaks and ensure an adequate supply of gas.
4. If the window is torn, the anode wires are likely to be broken as
well, shorting against the detector. Replace broken wires, clean
the lacquer thinner, then bake at 93 °C (200 °F).
5. Humidity can also be a problem for proportional detectors. Dry
and/or check the desiccants.