File:Split-anode magnetron.jpg

From Wikimedia Commons, the free media repository
Jump to navigation Jump to search

Split-anode_magnetron.jpg (345 × 258 pixels, file size: 15 KB, MIME type: image/jpeg)

Captions

Captions

Add a one-line explanation of what this file represents

Summary

[edit]
Description
English: Split-anode magnetron tube, an obsolete microwave vacuum tube invented by Albert Hull at General Electric in 1920. One of the first oscillators that could produce frequencies in the gigahertz range, it was used until the modern cavity magnetron was invented in 1940. This tube, used in 1935 in early German experiments in radar was manufactured by AEG/Telefunken and could generate 10 centimeter (3 GHz) microwaves. The image on the left shows the bare tube, about 11 cm tall; on the right shows the tube mounted for use between the poles of a strong permanent magnet.

Alterations to image: combined two separate images
Date
Source Retrieved October 24, 2014 from "Microwaves to detect aircraft" in Electronics magazine, McGraw-Hill Publishing Co., New York, Vol. 8, No. 9, September 1935, p. 18 on http://www.americanradiohistory.com
Author Unknown authorUnknown author
Permission
(Reusing this file)
This 1935 issue of Electronics magazine would have the copyright renewed in 1963. 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 1962, 1963, and 1964 show no renewal entries for Electronics. Therefore the copyright was not renewed and it is in the public domain.

Licensing

[edit]
Public domain
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.

العربية  Deutsch  English  español  français  galego  italiano  日本語  한국어  македонски  português  português do Brasil  русский  sicilianu  slovenščina  українська  简体中文  繁體中文  +/−

Flag of the United States
Flag of the United States

File history

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

Date/TimeThumbnailDimensionsUserComment
current07:49, 26 May 2015Thumbnail for version as of 07:49, 26 May 2015345 × 258 (15 KB)Chetvorno (talk | contribs)User created page with UploadWizard

The following page uses this file:

File usage on other wikis

The following other wikis use this file:

Metadata