File:National_Guard_operating_portable_radio_station_1922.jpg
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Summary
DescriptionNational Guard operating portable radio station 1922.jpg |
English: A portable military wireless station in 1922, operated by members of the 101st Signal Battalion, 2nd Corps, US National Guard Signal Corps, on field training near Peekskill, New York. Two guardsmen crank a hand-powered electric generator (left) as a third (center) operates an early vacuum tube transmitter sending text messages in Morse code using a telegraph key. The source (p. 58) says the equipment is an SCR-99, which can transmit on wavelengths between 900 m (330 kHz) and 1500 m (200 kHz). It uses VT-1 triodes for receiving and VT-2 triodes for transmitting, and has a range of about 100 miles with 320 V on the transmitting tubes. Caption: TRANSMITTING IN THE FIELD: The power for operating this equipment is furnished by the hand generator. Note the collapsible metal mast that serves as a support for an umbrella antenna |
Date | |
Source | Retrieved August 27, 2013 from Alfred M. Caddell, "Radio fans who are paid to learn" in Popular Radio, Popular Radio Inc., New York, Vol. 2, No. 1, September 1022, p. 53 on Google Books |
Author | Alfred M. Caddell |
Licensing
Public domainPublic domainfalsefalse |
This media file is in the public domain in the United States. This applies to U.S. works where the copyright has expired, often because its first publication occurred prior to January 1, 1929, and if not then due to lack of notice or renewal. See this page for further explanation.
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This image might not be in the public domain outside of the United States; this especially applies in the countries and areas that do not apply the rule of the shorter term for US works, such as Canada, Mainland China (not Hong Kong or Macao), Germany, Mexico, and Switzerland. The creator and year of publication are essential information and must be provided. See Wikipedia:Public domain and Wikipedia:Copyrights for more details.
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Items portrayed in this file
depicts
September 1922Gregorian
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Date/Time | Thumbnail | Dimensions | User | Comment | |
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current | 08:34, 19 January 2014 | 1,344 × 1,038 (153 KB) | Chetvorno | User created page with UploadWizard |
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