THE COMPANDOR 



329 



end is shown. The compandor circuits are indicated in their relation 

 to the subscriber, the toll switchboard, the vodas and privacy ap- 

 paratus, and the radio transmitter and receiver. ^ A meter located at 

 the point designated A would indicate the full range of applied volumes, 

 at B, the controlled volumes and at C, the compressed speech signals. 



Fig. 8 — Experimental installation of compandor at New York. 



When the United States subscriber talks, electrical waves set up 

 by his voice pass over a wire line to the toll switchboard. They then 

 divide in a hybrid set ; part of the energy is dissipated in the output of 

 a receiving repeater and part is amplified by a transmitting repeater 

 whose gain is controlled by noting the reading of a volume indicator at 



