GB257611A - - Google Patents

Abstract

257,611. Wired Radio, Inc., (Assignees of Duncan, R. D.). Aug. 25, 1925, [Convention date]. Wired-wireless systems. - In a wired wireless broadcasting system, means are provided at selected points in the feeders of the system to indicate at the transmitting station the energy level. Fig. 2 shows one, two, and three phase feeders 3, 4, and 2 respectively of a power distribution system which may be branch low tension power feeders fed from a hightension main. The high frequency supply from leads 14, 15, 16 may be single phase or polyphase and adjustably coupled to the feeders: or other control apparatus 24 - - 27 may be employed to vary the high frequency power introduced into each of the feeders. The apparatus for indicating the energy level may be placed at the end of the feeder or at the " electrical centre " and may comprise for each phase receiving circuits 28, 31, 32, 35 and a detector 38 which may be a crystal. The received energy is transmitted through a transformer 44, line 10 and amplifier 48 to the transmitting station and operates an ammeter 51 while a jack 52 allows telephones to be plugged in to determine quality which may be compared with a standard source of signals from the studio supplied to jack 63. In a modification Fig. 3, the carrier is rectified and applied through a choke 64 over a line 65 to an ammeter 66 at the transmitting station so that an indication is given when no modulation is taking place. When a two channel service is supplied the indicating apparatus is duplicated each set being tuned to one of the carrier frequencies used.