Triggering identification unit responding to specific frequency signal

摘要

An electronic trigger unit of the type used in games has a microphone supplied from a remote transmitter. The receiver module has a fitter input stage that eliminates background noise in the signal transmitted to a signal decoder. The decoder outputs coupled to exclusive-OR logic gates. Other inputs are provided by switches that allow a particular signal code to be set. For the set combination a NOR gate triggers a transistor to activate the indicator (7) signalling identification of the input signal.