page_title: April 1927
hierarchical_section_title: April 1927
caption_attribution_description: 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television technologies never achieved images of sufficiently high quality to catch on with the public, and were superseded by electronic scan television broadcasts in the 1930s.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&amp;I Television Receiver on Commons: Image:Science and Invention Nov 1928 Cover 2.jpg Image:Science and Invention Nov 1928 pg578.png Image:Science and Invention Nov 1928 pg618.png This photo cropped from page 618. Image:Science and Invention Nov 1928 pg619.png Image:Science and Invention Nov 1928 pg620.png Image:Science and Invention Nov 1928 pg632.png Image:Science and Invention Nov 1928 pg634.png Image:Science and Invention Nov 1928 pg636.png 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.
context_page_description: The following events occurred in April 1927:
context_section_description: The following events occurred in April 1927:
caption: April 7, 1927: Bell Telephone demonstrates new "television"
exif: {"Image ImageWidth": "2276", "Image ImageLength": "1267", "Image BitsPerSample": "8", "Image Compression": "LZW", "Image PhotometricInterpretation": "1", "Image ImageDescription": "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. \n\nScience and Invention, November 1928. Volume 16 Number 7.  Photo from page 618.", "Image Orientation": "Horizontal (normal)", "Image SamplesPerPixel": "1", "Image XResolution": "150", "Image YResolution": "150", "Image ResolutionUnit": "Pixels/Inch", "Image Software": "Adobe Photoshop Elements 5.0 Windows", "Image DateTime": "2008:08:09 10:36:02", "Image Copyright": "The copyright on the magazine was not renewed and it is in the public domain.\n\nPublished October 10, 1928 by Experimenter Publishing. New York, NY.", "Image ExifOffset": "692", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "72", "Thumbnail YResolution": "72", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "830", "Thumbnail JPEGInterchangeFormatLength": "6399", "EXIF ColorSpace": "Uncalibrated", "EXIF ExifImageWidth": "1138", "EXIF ExifImageLength": "633"}