File:Transmitter of CKAC Montreal 1924.jpg
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Transmitter_of_CKAC_Montreal_1924.jpg (415 × 572 pixels, file size: 48 KB, MIME type: image/jpeg)
Captions
Captions
Early AM broadcasting transmitter, 1922
Summary
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| Description |
English: First transmitter of AM radio station CKAC, Montreal, Canada, which began broadcasting October 2, 1922 on 730 kHz at a power of 7.5 kilowatts. Owned by the newspaper La Presse, it was the first Francophone radio station in North America. The early triode output tubes were the size of footballs to dissipate the waste heat. |
| Date | |
| Source | Retrieved July 14, 2014 from Radio News magazine, Experimenter Publishing Co., New York, Vol. 6, No. 6, December 1924, p. 911 on http://www.americanradiohistory.com archive |
| Author | Unknown author |
| Permission (Reusing this file) |
This 1924 issue of Radio News magazine would have the copyright renewed in 1952. Online page scans of the Catalog of Copyright Entries, published by the US Copyright Office can be found here. Search of the Renewals for Periodicals for 1951, 1952, and 1953 show no renewal entries for Radio News. Therefore the copyright was not renewed and it is in the public domain. |
Licensing
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This work is in the public domain because it was published in the United States between 1929 and 1963, and although there may or may not have been a copyright notice, the copyright was not renewed. For further explanation, see Commons:Hirtle chart and the copyright renewal logs. Note that it may still be copyrighted in jurisdictions that do not apply the rule of the shorter term for US works (depending on the date of the author's death), such as Canada (70 years p.m.a.), Mainland China (50 years p.m.a., not Hong Kong or Macao), Germany (70 years p.m.a.), Mexico (100 years p.m.a.), Switzerland (70 years p.m.a.), and other countries with individual treaties.
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| Date/Time | Thumbnail | Dimensions | User | Comment | |
|---|---|---|---|---|---|
| current | 04:58, 21 September 2015 | | 415 × 572 (48 KB) | Chetvorno (talk | contribs) | User created page with UploadWizard |
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