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File:Amateur T cage antenna 2BML 1922.jpg

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Summary

Description
English: Transmitting antenna of amateur radio station 2BML and 2EH in 1922, belonging to the Radio Engineers Club of Riverhead, New York, USA. This type of wire antenna, called a cage T antenna, was commonly used for transmitting on MF and LF frequencies. It consists of a conductor in the form of a "T", 60 ft high and 90 ft wide, suspended beween two masts. The conductor is made of a "cage" of six parallel wires held apart with wood spreaders. The vertical line extending upward from the transmitter shack radiates the radio waves, while the horizontal part is a capacitive "top-load" which increases the current in the vertical part. The multiwire "cage" construction serves to increases the capacitance to ground and decrease the resistance, further increasing the antenna current and radiated power. The ground of the transmitter was attached to a "counterpoise", a horizontal wire suspended a few feet above the ground under the antenna. It achieved transatlantic contacts to Scotland on 200 meters (1.5 MHz) at a radiated power of 440W. The antenna resistance is 7 ohms and the efficiency is 67%.

Alterations to image: Removed dark tint to sky in left side of photo using GIMP editor.
Date
Source Retrieved March 12, 2014 from Robert C. Higgy, "The Successful Transatlantic Stations", QST magazine, American Radio Relay League, Inc., Hartford, Conn., Vol. 5, No. 8, March 1922, p. 11 on Google Books
Author Robert C. Higgy
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Amateur T cage antenna 2BML 1922-colorized.jpg

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March 1922Gregorian

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Date/TimeThumbnailDimensionsUserComment
current14:52, 30 September 2020Thumbnail for version as of 14:52, 30 September 20201,277 × 1,049 (165 KB)HohumUpload colourised images separately
05:15, 22 June 2020Thumbnail for version as of 05:15, 22 June 20201,095 × 899 (168 KB)F1jmmColorisation
10:58, 13 March 2014Thumbnail for version as of 10:58, 13 March 20141,277 × 1,049 (165 KB)ChetvornoUser created page with UploadWizard
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