File:Rack mounted telephone equipment (1923).png
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Summary
| Description |
English: Diagram of w:relay racks with telephone equipment mount on vertical rails. This system was standardized for use in Bell System central offices in 1922-23.
Original caption: "Fig. 28 — General View Showing Typical Group of Equipment Units Employing Panel Mounting Method" |
| Date | |
| Source |
Demarest, Charles S. (July 1923). "Telephone Equipment for Long Cable Circuits". Bell System Technical Journal. Vol. 2 no. 3. New York: American Telephone and Telegraph Company. p. 138. [1] |
| Author | Charles S. Demarest |
Licensing
|
This work is in the public domain in the United States because it was published (or registered with the U.S. Copyright Office) before January 1, 1930.
 Public domain works must be out of copyright in both the United States and in the source country of the work in order to be hosted on the Commons. If the work is not a U.S. work, the file must have an additional copyright tag indicating the copyright status in the source country.
Note: This tag should not be used for sound recordings. |
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| Date/Time | Thumbnail | Dimensions | User | Comment | |
|---|---|---|---|---|---|
| current | 18:19, 9 December 2019 | | 670 × 839 (407 KB) | wikimediacommons>Mu301 | User created page with UploadWizard |
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