Multiplex system having digital coded power line signals

摘要

An electronic control circuit is disclosed herein for transmitting a coded signal and operating power to a selected one of a plurality of receivers via a single pair of wires. The control circuit includes a transmitter coupled to a source of AC line voltage and having a coding network for coding signals consisting of missing cycles from the AC line voltage so that a resultant output signal constitutes both the coded signal to the receiver and the operating power for the same receiver. Timing networks are included in the transmitter control circuit for allowing the output signals to be transmitted to the selected receiver only within a brief time interval. Reset networks are interconnected within the transmitter control circuit and the timing networks for returning the transmitter control circuit back to a condition of awaiting asynchronous commands for forwarding to a selected receiver via the single pair of wires.