. Automatic telephony; a comprehensive treatise on automatic and semi-automatic systems . 3rd. Office- 45000-4800Q | Fig. 22.—One first-selector level for two offices r I Office -42 OOP- 43000 We may let two offices share one level of first selectors. (Fig. 22.)Assume a 100,000-line system. There are five digits in the call illustration concerns the fourth level. Numbers in the 45, 46, 47 and 48 thousands are given to one office(at the left). Numbers in the 42 and 43 thousands are placed in anotheroffice, usually near by. From the first selector banks in the 45,000-48,000 off
. Automatic telephony; a comprehensive treatise on automatic and semi-automatic systems . 3rd. Office- 45000-4800Q | Fig. 22.—One first-selector level for two offices r I Office -42 OOP- 43000 We may let two offices share one level of first selectors. (Fig. 22.)Assume a 100,000-line system. There are five digits in the call illustration concerns the fourth level. Numbers in the 45, 46, 47 and 48 thousands are given to one office(at the left). Numbers in the 42 and 43 thousands are placed in anotheroffice, usually near by. From the first selector banks in the 45,000-48,000 office the trunks run to other offices, except that the fourth level islocal. These fourth-level trunks run to local second selectors. Levels five to eight on the second selectors run to third selectorswhich are grouped according to thousands. Their banks in turn leadto connectors by hundreds. Incoming trunks from other offices in theexchange terminate on incoming second selectors whose banks aremultipled with the local second selectors. Levels two and three are trunked out to the associated offic
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Keywords: ., bookcentury1900, bookdecade1920, booksubjecttelephone, bookyear19
