摘要 |
A security circuit includes a power supply and one or more modular switch units and a modular alarm unit. Each modular unit includes two standard multiple-conductor telephone jack sockets, with at least one conductor of each socket connected to the circuitry of the unit, with all of the other conductors of one socket being respectively directly connected in-line to the corresponding conductors of the other socket. The modular units are interconnectable with standard telephone connector cables having modular telephone jack plugs mateable with the sockets. The power supply may be a battery which may also be provided with modular telephone jack sockets. Alternatively, the circuit may be powered from the RS-232 serial port of a personal computer, the telephone connector cable being coupled thereto through a standard adapter. Different versions of switch units and alarm units are disclosed. Series circuits are terminated with a spiral terminator plug.
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