Recent content by old-ham

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    How to Detect What Frequency a Radio Has Tuned

    Yes not only can it be done; but MI5 in England were doing it against the Soviets including the KGB in London in the 1950s and 60. Target was Soviet Security Hand Held VHF/UHF radios. The details are in Peter Wright's book Spy Catcher. Basically employs a sweep signal and you get a dip in the...