Accession Number : ADD014887

Title :   R. F. Lockout Circuit for Electronic Locking System.

Descriptive Note : Patent, Filed 24 Nov 89, patented 26 Feb 91,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Becker, Earl M , Jr ; Miller, Allen

Report Date : 26 Feb 1991

Pagination or Media Count : 8

Abstract : An electronics lockout circuit including an antenna adapted to receive radio frequency signals from a transmitter, and a radio frequency detector circuit which converts the radio frequency signals into a first direct current voltage indicative of the relative strength of the field resulting from the radio frequency signals. The first direct current voltage is supplied to a trigger circuit which compares this direct current voltage to an adjustable direct current reference voltage and provides a second direct current voltage at the output thereof whenever the amplitude of the first direct current voltage exceeds the amplitude of the reference voltage provided by the comparator circuit is supplied to a disconnect relay circuit which upon receiving a signal from the electronic control unit of an electronic combination lock during the time period the second direct current voltage is present isolates the door strike coil of a security door from the electronic control unit. This prevents signals falsely generated by the electronic control unit because of radio frequency signals in the vicinity of the electronic control unit because of radio frequency signals in the vicinity of the electronic control unit from energizing the door strike coil and thereby accidentally opening a security door.

Descriptors :   CIRCUITS, COMPARATORS, CONTROL SYSTEMS, DETECTORS, DIRECT CURRENT, DISCONNECT FITTINGS, DOORS, ELECTRONIC EQUIPMENT, ELECTRONICS, LOCKING(MECHANICS), RADIO SIGNALS, RADIOFREQUENCY, RELAYS, SECURITY, STRENGTH(GENERAL), VOLTAGE

Subject Categories : Radio Communications

Distribution Statement : APPROVED FOR PUBLIC RELEASE