Dumont Cathautograph Apparatus
date: label: date made
content: ca 1933
name: label: maker
content: DuMont Company
notes: label: Description (Brief)
content: Includes power supply and hood. Manufacture: Dumont Laboratory. Designed to send messages for CRT viewing at a time when television camera development was still in its infancy. The procedure was to vary horizontal and vertical deflection voltages on a CRT by a variable resistance method employing a "writing" pen. The viewer would then observe beam force-out on the CRT screen that would correspond to the transmitted writing. By using high persistence phosphors, messages could be retained on the screen for a period before the next transmissions were received. This invention is a CRT variation of the Telauthgraph and was patented under that title in 1935A later patent under the title of cathautograph was issued in 1940 and is substantially this instrument, though the CRT is missing from the case. Initial experiments were done in 1932-33. In September 1933 a cathautograph system was demonstrated at the National Electrical Exposition held at Madison Square Garden. A 9" CRT was used in that instance. References: A. B. Dumont notebook, page 46, 30 Sept 1933; US Patent 2000014 and 2185705; "Radio Pen", Popular Science, December 1933.
label: Location
content: Currently not on view
setName: label: See more items in
content: Work and Industry: Electricity
creditLine: label: Credit Line
content: from Ethel DuMont
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: EM.327760
label: catalog number
content: 327760
label: accession number
content: 270106
objectType: label: Object Name
content: Cathautograph
physicalDescription: label: Measurements
content: tablet: 5 in x 6 1/2 in x 23 in; 12.7 cm x 16.51 cm x 58.42 cm
label: Measurements
content: power supply: 9 1/2 in x 13 in x 10 1/4 in; 24.13 cm x 33.02 cm x 26.035 cm