. The Bell System technical journal . 742 BELL SYSTEM TECHNICAL JOURNAL. Fig. 4. THE NEW YORK-LONDON TELEPHONE CIRCUIT 743 England.^ Were it not for the use of the voice-operated devices, thiswould result in a very strong echo being returned to the local talkerwith disconcerting effects, and, dependent upon the adjustment ofother parts of the circuit, might even result in violent singing of thecircuit. Referring again to Fig. 2 {A), it will be seen that there are threepaths capable of giving rise to objectionable echoes or singing, onepath at each end of the circuit through the wire lines, rad
. The Bell System technical journal . 742 BELL SYSTEM TECHNICAL JOURNAL. Fig. 4. THE NEW YORK-LONDON TELEPHONE CIRCUIT 743 England.^ Were it not for the use of the voice-operated devices, thiswould result in a very strong echo being returned to the local talkerwith disconcerting effects, and, dependent upon the adjustment ofother parts of the circuit, might even result in violent singing of thecircuit. Referring again to Fig. 2 {A), it will be seen that there are threepaths capable of giving rise to objectionable echoes or singing, onepath at each end of the circuit through the wire lines, radio transmitterand local receiver, and a third path from end to end of the circuit andback again. The first two paths are introduced by using the samefrequency band for transmission in both directions. The third pathwhich depends upon the impedance unbalance between the two-wirelines at the terminals and their respective networks is similar to theone which gives rise to echoes in long four-wire land telephone three paths are affected by the amplification a
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Keywords: ., bookcentury1900, bookdecade1920, booksubjecttechnology, bookyear1
