This is a file from the Wikimedia Commons

File:Wire T antenna station WBZ 1925.jpg

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

Original file(824 × 1,064 pixels, file size: 118 KB, MIME type: image/jpeg)


English: Multiwire T aerial of radio station WBZ in Springfield, Massachusetts, USA, in 1925. Licensed on September 15, 1921, it is claimed to be the first commercially licensed broadcast station in the US (although other stations like WWJ and KDKA had been broadcasting under other licenses for several years). Located at the Westinghouse plant in East Springfield, it broadcast on a wavelength of 360 meters (833 kHz) with a power of 2000 W. The antenna is typical of the wire antennas used for mediumwave broadcasting in the 1920s. The vertical wire connecting to the middle of the antenna is the radiating element, and the multiwire horizontal part is the capacitive "top load"; its function is to increase the oscillating currents in the vertical wire to increase the radiated power.
Source Retrieved March 7, 2014 from Popular Radio magazine, Popular Radio, Inc., New York, Vol. 7, No. 6, June 1925, p. 555 on American Radio History website
Author Unknown authorUnknown author
(Reusing this file)
This 1925 issue of Popular Radio magazine would have the copyright renewed in 1953. Online page scans of the Catalog of Copyright Entries, published by the US Copyright Office can be found here. [1] Search of the Renewals for Periodicals for 1952, 1953 and 1954 show no renewal entries for Radio World. Therefore the magazine's copyright was not renewed and it is in the public domain.


Public domain
This work is in the public domain because it was published in the United States between 1926 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. 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 (50 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.

العربيَّة | Deutsch | English | español | français | galego | italiano | 日本語 | 한국어 | македонски | português | português do Brasil | русский | sicilianu | українська | 中文(简体)‎ | 中文(台灣)‎ | +/−

Flag of the United States


Add a one-line explanation of what this file represents

Items portrayed in this file


June 1925Gregorian

File history

Click on a date/time to view the file as it appeared at that time.

current10:14, 11 March 2014Thumbnail for version as of 10:14, 11 March 2014824 × 1,064 (118 KB)ChetvornoUser created page with UploadWizard
The following pages on the English Wikipedia use this file (pages on other projects are not listed):