File:Telephone switchboard cross-switching (Rankin Kennedy, Electrical Installations, Vol V, 1903).jpg
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Summary
This is in fact a manual crossbar. It has the capacity of four subscriber lines (top) and four horizontal talking paths (albeit not needed for four subscribers). The fifth crossbar is the operator circuit, and at the bottom is the ground bar for enabling the signal indicators for idle subscribers.
Copyright status:
public domain
Source:
Scan from Kennedy, Rankin (1903 edition (five volumes) of pre-1903 four volume edition.) Electrical Installations, vol. V, London: Caxton
File history
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Date/Time | Thumbnail | Dimensions | User | Comment | |
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current | 04:01, 31 July 2021 | 553 × 712 (45 KB) | Thales (talk | contribs) | This is in fact a manual crossbar. It has the capacity of four subscriber lines (top) and four horizontal talking paths (albeit not needed for four subscribers). The fifth crossbar is the operator circuit, and at the bottom is the ground bar for enabli... |
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