Audion_vacuum_tube_advertisement.png
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Summary
| Description |
English:
Advertisement for the
Audion
vacuum tube
invented by
Lee De Forest
in 1907, from
The Electrical Experimenter
magazine, August 1916, volume 4, number 4, page 228. This was the first
triode
, the first vacuum tube that could
amplify
electrical signals. It was used by amateur experimenters as well as commercial companies to build the first amplifying radio receivers, as indicated in the advertisement. By the time of this advertisement, improved versions were being sold by General Electric and other manufacturers, as shown by De Forest's efforts to differentiate his product.
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| Date | Magazine published August 1916; this page scanned February 2008. | |||
| Source |
English:
The Electrical Experimenter
magazine, August 1916, volume 4, number 4, page 228. This page was scanned by
Swtpc6800
on an Epson Perfection 1240U at 300 dpi with half-tone de-screening enabled, and stored as an TIFF. The image was cropped and touched up in Adobe Photo Elements 5.0. This copy was saved as a 150-dpi PNG file.
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| Author | Published by Experimenter Publishing Company Inc,. 233 Fulton Street, New York, N.Y. Hugo Gernsback, President; Sidney Gernsback, Treasurer; Milton Hymes, Secretary. | |||
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Permission
( Reusing this file ) |
This magazine was published in the United States before 1923 and is in the public domain. | |||
| Other versions |
|
Licensing
|
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. |