KirjeldusScience and Invention Television 1928.jpg
English: A woman watching an early homemade experimental mechanical television receiver in 1928, from Hugo Gernsback's magazine Science and Invention. During the 1920s some radio stations began broadcasting experimental television programs, which could be viewed by mechanical "televisor" receivers like this one. The video signal from the receiver (left) is applied to a neon lamp in the viewer (right). In front of the lamp a metal disk with holes rotates, creating the scan lines of the image. This created a dim monochrome orange image 1.5 inches (4 cm) square with 48 scan lines at 7.5 frames per second, visible within the viewing cone, which the woman is watching. These mechanical-scan television technologies never achieved images of sufficiently high quality to catch on with the public, and were superseded by electronic scan television broadcasts in the 1930s.
Page scans of the above article How to build the S&I Television Receiver on Commons:
The page numbers were on an annual basis, not per issue. This issue had pages 577 to 672. The magazine is 8.5 by 11.5 inches.
Kuupäev
November 1928. This page scanned August 2008.
Allikas
Science and Invention magazine, November 1928, Volume 16, Number 7, cover, published by Experimenter Publishing Co., New York, NY. This page was scanned by User:Swtpc6800 on an Epson Perfection 1240U at 300 dpi with half-tone de-screening enabled and stored as TIFF. The image was cropped and touched up in Adobe Photo Elements 5.0. This copy saved as a 150 dpi JPG.
This 1928 issue of Science and Invention would have the copyright renewed in 1955. Online page scans of the Catalog of Copyright Entries, published by the US Copyright Office can be found here. http://onlinebooks.library.upenn.edu/cce/ The search of the Renewals for Periodicals for 1954, 1955 and 1956 show no renewal entries for Science and Invention. Therefore the copyright on the magazine was not renewed and it is in the public domain. Science and Invention ceased publication with the August 1931 issue. A search of the copyright renewal records from 1951 to 1959 shows no entries for Science and Invention. All issues are in the public domain.
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 (70 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.
Selleks et avaliku omandi teost saaks Commonsis hoida, peab selle autoriõiguse kehtivus olema lõppenud nii Ühendriikides kui ka päritoluriigis. Kui see ole Ühendriikide teos, siis peab selle juures olema ka autoriõiguse märgis, mis nätab, milline on teose autoriõiguslik staatus päritoluriigis.PD-USÜhendriikides avalikus omandis//commons.wikimedia.org/wiki/File:Science_and_Invention_Television_1928.jpg
Faili ajalugu
Klõpsa kuupäeva ja kellaaega, et näha sel ajahetkel kasutusel olnud failiversiooni.
A slight adjustment of the rheostats and the picture come in clearly. This photo shows the complete television receiver connected to an ordinary radio set. The picture is seen in the cone. == Summary == {{Information | Description= A slight adjustment
See fail sisaldab lisateavet, mille on tõenäoliselt lisanud digikaamera või skanner.
Kui faili on rakendustarkvaraga töödeldud, võib osa andmeid olla muudetud või täielikult eemaldatud.
Pildi pealkiri
A slight adjustment of the rheostats and the picture come in clearly. This photo shows the complete television receiver connected to an ordinary radio set. The picture is seen in the cone.
Science and Invention, November 1928. Volume 16 Number 7. Photo from page 618.
Autoriõiguse omanik
The copyright on the magazine was not renewed and it is in the public domain.
Published October 10, 1928 by Experimenter Publishing. New York, NY.