. The Bell System technical journal . The method is similar to that used on other types ofcircuits, but includes a number of simplifications. The number oftubes has been reduced, and the vibrating relays used in the older typecircuits have been replaced by copper oxide rectifiers and simple requiring little maintenance. When 20-cycle ringing current isreceived from the switchboard, the frequency of the carrier supplyoscillator is shifted by 1000 cycles and its output is interrupted at a20-cycle rate, and applied to the input of the transmitting the receiving end this ap
. The Bell System technical journal . The method is similar to that used on other types ofcircuits, but includes a number of simplifications. The number oftubes has been reduced, and the vibrating relays used in the older typecircuits have been replaced by copper oxide rectifiers and simple requiring little maintenance. When 20-cycle ringing current isreceived from the switchboard, the frequency of the carrier supplyoscillator is shifted by 1000 cycles and its output is interrupted at a20-cycle rate, and applied to the input of the transmitting the receiving end this appears at the input of the signal receivingcircuit as a 1000-cycle current interrupted at a 20-cycle rate. It isthen demodulated in a copper oxide rectifier and the resulting 20-cyclecurrent is amplified and applied to a second rectifier the output ofwhich is connected to a d-c. relay. Operation of this relay causes20-cycle current from a local source to be sent toward the switchboard. NEW SINGLE CHANNEL CARRIER TELEPHONE SYSTEAI 167. 168 BELL SYSTEM TECHNICAL JOURNAL
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Keywords: ., bookcentury1900, bookdecade1920, booksubjecttechnology, bookyear1
