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 43
office. Fig. 24.—Traffic divided at two intermediate offices. he pulls any digit from 5 to 8 inclusive, that selector will trunkthe call to the upper office. Again, the traffic may be divided at two intermediate offices. (Fig.24.) In this case the traffic from offices at the left is most… … Office No.33Office No.32Off fee No.31Office No. 23 Off ice No. 22Office No. 2/Office No. 13 Office No. 12Office No. II Fig. 25.—Direct trunks with first and second selectors. Another way of handling the large exchange is to provide first selectorsand second selectors in each office, with direct…
Telephone
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