Carrier-wave telephony over power lines: Early history [History of Communications]

In this column we discuss the early history of power line voice communication, beginning in 1918 and continuing until the early 1930s. We note that these developments were based on the 1910 demonstration by Major George Squier of the United States Army Signal Corps of his "wired wireless" technique for transmitting multiple telephone channels over one pair of wires. Power companies world-wide picked up on this carrier-wave telephony technique for use over power lines, with electrical manufacturing companies such as GE and Westinghouse in the United States and Telefunken in Germany, among others, then developing a variety of systems for this purpose. By 1930, the technique had reached a period of maturity, with 1000 systems installed throughout Europe and the United States.