03962547 is referenced by 79 patents and cites 4 patents.

Apparatus for connecting separate transmitters of a carrier communication system to the same location on a power distribution line. A low-power transmitter is connected to the primary winding of an interconnecting transformer. The secondary winding of the interconnecting transformer is connected between a high-power transmitter and, through the primary winding of a coupling transformer, to ground potential. The secondary winding of the coupling transformer is coupled to the power distribution line. A voltage limiting device is connected across the secondary winding of the interconnecting transformer. The output of the high-power transmitter is directed across the voltage limiting device to the coupling transformer where it is applied to the distribution line. When the low-power transmitter is turned on and the drive signal to the high-power transmitter is turned off, the power from the low-power transmitter is transferred to the secondary winding of the interconnecting transformer and to the coupling transformer where it is applied to the distribution line. The high-power transmitter represents a virtual ground potential when it is not transmitting, thereby providing a closed circuit path for the power delivered by the low-power transmitter.

Title
Repeater coupler for power line communication systems
Application Number
5/580861
Publication Number
3962547
Application Date
May 27, 1975
Publication Date
June 8, 1976
Inventor
Tamas I Pattantyus Abraham
Pittsburgh
PA, US
Agent
D R Lackey
Assignee
Westinghouse Electric Corporation
PA, US
IPC
H04H 1/08
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