Accession Number : ADD002480

Title :   Periodic Signal Detector.

Descriptive Note : Patent,


Personal Author(s) : Mullen,Walter W , Jr ; Hooks,George L , III

Report Date : 18 Nov 1975

Pagination or Media Count : 10

Abstract : A periodic signal detector is disclosed which may be incorporated to an advantage in a voice actuated communication system. It comprises a series connected low pass filter, limiter, and bistable multivibrator, the outputs of the latter of which are respectively connected to the inputs of a pair of ramp generators. A differential comparator detects the difference in the output voltage from said pair of ramp generators and uses it to timely trigger a first monostable multivibrator. A shift register and AND gate extracts a desired program of successive binary signals from the output signal from said first monostable multivibrator. A second monostable multivibrator, triggered by one of the outputs of said bistable multivibrator, in turn, resets said ramp generators and timely shifts said shift register. The output of said AND gate is used to key a transmitter or some other utilization apparatus.

Descriptors :   *Voice communications, *Signal processing, *Patents, Shift registers, Logic circuits, Low pass filters, Bistable devices, Multivibrators

Subject Categories : Voice Communications

Distribution Statement : APPROVED FOR PUBLIC RELEASE