580 



BELL SYSTEM TECHNICAL JOURNAL 



\ ^ VENTILATION LOUVER 



POWER SERVICE (NEAR FLOOR) 



„ CABINET 



1-2 

 POWER BAYS ^ 



L-,---V!l li 



Z 1 



ULTIMATE BATTERY 



(24-HOUR RESERVE FOR 



100 REPEATERS) 



.WRITING SHELF 



EAST-WEST EQUIPMENT 



I (OUT) 



2(lN) 



\\\ 



8 



DC 



DC 



3'-2" 



fzi] /° 



EAST-WEST FLAT-GAIN FUSE 1-21 22-42 43-63 BYPASS 64-64 ...L , 



CON- PANELS ^ ' AMPLI- cVcoc 



AMPLIFIERS FIER '^'^^^ 



'^ "^ 85-101 

 WEST-EAST 3 4 5 6 7 8 9 i 



--.I II II 1 V 



_j| It Ji J 4 



TROLLERS 

 3 

 C 



1-21 22-42 43-63 BY PASS 64-84 



V ' AMPLI- 



AMPLIFIERS FIER 



1 I' 



EXHAUST FAN 

 NEAR CEILING 



Fig. 17 — Floor plan arrangement of equipment for 100 systems at an auxiliary 



repeater station. 



into account the estimated growth of carrier ampHfier equipment re- 

 quirements for that period. 



The entire voltage of the battery is used to furnish plate supply for 

 the amplifier tubes. The 70-cell battery is arranged in seven groups 

 of 10 cells each and taps are taken from each group to supply current 

 for the heaters of the tubes of each amplifier. To prevent an uneven 

 drain, amplifiers are connected across the battery in multiples of seven. 

 In case the number of amplifiers installed is not an even multiple of 

 seven, dummy load resistances are connected as required, in lieu of 

 amplifiers to fill out the unequipped multiple. 



The controller power supply bay contains apparatus for the 140-volt 

 d-c pilot wire bridge supply and 55-volt, 60-cycle a-c supply. An 

 emergency rotary converter, which automatically provides 110-volt, 

 60-cycle a-c supply during outside power failure, and operates inter- 

 mittently from the battery, also is mounted in this bay. 



