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 46
rdless of districts. (Fig. 29.) As long as we are gathering together TRUNKING 29 originating traffic, we may combine at any suitable place the trunks whichcome from any offices by using second selectors to function as a switchingoffice. It gives great flexibility to the system. Offices and… … Fig. 28.—Combining traffic from one group of offices to another group. thought that districts 2 and 3 would ultimately need ten 10,000-lineoffices each. Accordingly, offices 21, 22, 23, etc. to 29 and 20 were setaside for district 2 and offices 31, 32, 33, etc. to 39 and 30 were set asidefor…
Telephone
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