File:Rotor of Alexanderson alternator.jpg
From Wikimedia Commons, the free media repository
Jump to navigation
Jump to search
Size of this preview: 800 × 499 pixels. Other resolutions: 320 × 200 pixels | 640 × 399 pixels | 1,024 × 639 pixels | 1,280 × 798 pixels | 1,863 × 1,162 pixels.
Original file (1,863 × 1,162 pixels, file size: 116 KB, MIME type: image/jpeg)
File information
Structured data
Captions
Summary
[edit]DescriptionRotor of Alexanderson alternator.jpg |
English: The rotor of a General Electric 200 kW Alexanderson alternator, a type of radio transmitter used from 1906 to 1930. The rotor consists of a disk made of high tensile magnetic steel with narrow slots cut in its periphery, creating a series of blades which form the magnetic "poles" of the machine. The slots are filled with bronze to give the rotor a smooth surface. The rotor has no conductive windings and the machine operates by induction. A stator with an equal number of poles around the periphery of the rotor creates a magnetic field axially through the side of the rotor. When the stator and rotor poles line up the magnetic flux through the pole increases. When the rotor poles are between two stator poles the magnetic flux decreases. This induces a radio frequency alternating current in the stator wondings. The rotor weighs 5500 lb. The air gap between the rotor and stator on each side is only 1 mm, maintained by a complicated thrust bearing system. It turned at 2170 RPM and the alternator transmitted at 22. 1 kHz. It was installed in September 1918 at RCA's New Brunswick, N.J. station Alterations to image: Removed aliasing artifacts (background grid of stripes) introduced by scanning halftone photo, using the Gimp FFT filter. |
Date | |
Source | Downloaded 3 October 2013 from Elmer E. Bucher (1920) Technical Description of the Alexanderson System, The Wireless Press, Inc., New York, p. 14, fig. 10 on Google Books |
Author | Elmer E. Bucher |
Licensing
[edit]Public domainPublic domainfalsefalse |
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.PD-1923Public domain in the United States//commons.wikimedia.org/wiki/File:Rotor_of_Alexanderson_alternator.jpg |
File history
Click on a date/time to view the file as it appeared at that time.
Date/Time | Thumbnail | Dimensions | User | Comment | |
---|---|---|---|---|---|
current | 21:38, 3 October 2013 | 1,863 × 1,162 (116 KB) | Chetvorno (talk | contribs) | User created page with UploadWizard |
You cannot overwrite this file.
File usage on Commons
There are no pages that use this file.
File usage on other wikis
The following other wikis use this file:
- Usage on en.wikipedia.org
Metadata
This file contains additional information such as Exif metadata which may have been added by the digital camera, scanner, or software program used to create or digitize it. If the file has been modified from its original state, some details such as the timestamp may not fully reflect those of the original file. The timestamp is only as accurate as the clock in the camera, and it may be completely wrong.
JPEG file comment | Created with GIMP |
---|
Hidden category: