File:Charles Apgar.png
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Summary
| Description |
English: Amateur radio operator w:Charles E. Apgar with his wax cylinder invention for recording w:wireless telegraphy transmissions. |
| Date | |
| Source | Reproduced in "The Secret Service of the Air". Popular Radio. New York: July 1922, page 167. |
| Author | Samuel Cohen |
Licensing
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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, 1929.
 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. |
File history
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| Date/Time | Thumbnail | Dimensions | User | Comment | |
|---|---|---|---|---|---|
| current | 20:45, 22 December 2019 | | 1,122 × 1,139 (856 KB) | Mu301 | User created page with UploadWizard |
File usage
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