2.5
THERMAL-RADIATION DETECTOR
The thermal-radiation detector consisted of a phototube, amplifier, and high- and
low-band-pass filters. The phototube output was produced by incident-thermal radiation from a nuclear device, lightning strokes, or other sources. This output was fed
to a high band-pass filter that passed only signals with a rise time similar to those
caused by nuclear detonations and to a low band-pass filter that passed only those signals with a duration typical of nuclear detonations. Thus, an incident thermal-radiation
signal had to have both a rise time and a duration typical of nuclear devices in order to
activate the thermal-radiation detector.
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