GB206715A - Improvements in or relating to repeating systems and apparatus therefor, particularly for telephone systems - Google Patents

Abstract

206,715. Western Electric Co., Ltd., (Western Electric Co., Inc.). Nov. 29, 1922. Repeating and amplifying systems.-A two-way repeater has a pair of relays, one of which is operated by current in each direction to render the repeater effective in that direction, and a loaded circuit is provided to delay the incoming signals when this is done. In one form, incoming current over the line 10, Fig. 1, energizes a relay 45 which supplies anode potential to a thermionic valve 14 over a relay 39 and a chokecoil 41, and current to the input transformer 13 is delayed by the loaded circuit 12 comprising series inductances and shunt condensers. The amplified signals pass to the line 23 through a transformer 20. The relay 52 which is operated by incoming current over the line 23 is ineffective to bring the corresponding valve 30 into action, since the circuit supplying anode potential is broken by the energization of the relay 39. In a second form, the line 70, Fig. 2, is connected directly to the repeating element 71, and part of the output current passes to a rectifier 73 and energizes relays 74, 75, thereby unbalancing a bridge 76 to allow the signals to pass to the line 77, and opening the circuit of the rectifier 78 to prevent retroaction. The loaded delay circuit 81 is inserted between the repeating element 71 and the bridge 76. The relay 74 may alternatively remove a shunt across the outgoing line.