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BELL SYSTEM TECHNICAL JOURNAL 



Floor plans suitable for the majority of offices are available and 

 reasonably standardized layouts of power equipment to operate certain 

 types of offices are found practicable. 



Improved Service 

 Improved operation of telephone equipment is being made possible 

 by more rigid requirements placed upon the power plant. Automatic 

 voltage regulators for ringing generators have been in use for some time 



Fig. 9 — 24- volt discharge lead filter. 800-ampere coil, four 1,200-mf. condensers 

 for use in suppressing generator and other equipment noises. 



and the new alternating-current — direct-current system is reducing 

 service troubles. Automatic voltage control equipment for charging 

 generators has been developed and is being introduced. This, together 

 with the full floating system of operating batteries, is capable of holding 

 the main power supply for the central offices at much closer voltage 

 limits than have been found practicable in the past, thus further 

 stabilizing transmission and contributing to even more reliable opera- 

 tion of relays and supervisory equipment. 



