Automatic telephony; a comprehensive treatise on automatic and semi-automatic systems (1921)
Smith, Arthur Bessey, b. 1875, Campbell, Wilson Lee · New York : McGraw-Hill · leaf 440
ith four digit numbers. Instead, fivefigure numbers should be used; i.e., the system should have an ultimatecapacity of 100,000 lines rather than 10,000. There would be twodisadvantages to the 100,000 line capacity system. 1. Third selectors would be added, increasing the first cost and… … Fig. 313.—Skeleton diagram of a system of three main offices, Main B, and D, andthree district stations A, C, and E. Neither of these are very serious disadvantages, and are outbalancedby the two advantages which would be: 1. Room in the numbering system for a large growth in all offices. 2. A…
Telephone
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