Field Strength Meter Circuit

Field Strength Meter Circuit FM / VHF / UHF

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Field Strength Meter Circuit, FM - VHF - UHF
This is the famous #016 “Bug-Sniffer” field strength meter circuit that was printed in Mick Tyners Book "Spook Book 1” that was engineered by John S. Wilson Jr. It is very sensitive and operates in virtually all bands up to the lower UHF bands. A regular digital voltmeter (uA) setting can be used in place of the 50uA meter.

Considered a masterpiece by all that have built it. The antenna can be anything from a stiff piece of wire about 8 to 10 inches long or a telescoping antenna when built in an enclosure. Just set the meter to scale with the calibrate and gain controls. It detects the smallest signals from the very low radio bands up to radiation from a microwave.

Useful for detecting low power bugging devices or powerful bugging transmitters. As the meter climbs, decrease the gain and the unit will lead you directly to the source of where the signal is being radiated.