Beaver County News | 1923-12-28 | Page 6 | Person may Listen and Converse at Same Time

Person May Listen and Converse at Same Time Conversations are being held daily over the 110,000-volt Keokuk Dam cables, between the Page Avenue substation sub-station of the Union Electric Light and Power company, St. Louis, and the St. Charles (Mo.) substation, by means of a wired-wlreless system perfected per-fected by Roy L. Glasgow, assistant professor of electrical engineering at Washington university, St. Louis. The apparatus devised by Professor Glasgow Glas-gow comprises a duplex system, whereby where-by two transmission wires are so used that a person may talk and listen at the same time, using an ordinary telephonic tele-phonic transmitter and receiver, and a delicate relay system by which the Incoming Impulse switches In a local current to ring a bell or light a lamp as a calling signal. The transmission set uses two five-watt tubes. Wires at each terminal are stretched about 500 feet parallel to the power cables, A feature of the relay system is a resistance re-sistance of 2,000,000 ohms.