Image: Westinghouse experimental 700 MHz transmitter 1932

Description: An experimental 700 MHz microwave transmitter on the roof of the Westinghouse office building in 1932, part of early research that resulted in microwave relay systems by the 1940s. The 16 inch waves radiated by the vertical dipole (right) are focused into a beam by the cylindrical parabolic reflector, which is received by another parabolic antenna a mile away. The microwaves were probably generated by a Split-anode magnetron, an obsolete vacuum tube oscillator that was one of the few sources of microwaves at that time.
Title: Westinghouse experimental 700 MHz transmitter 1932
Credit: Retrieved March 19, 2015 from Short Wave Craft magazine, Popular Book Co., New York, Vol. 2, No. 6, April 1932, p. 378 on http://www.americanradiohistory.com
Author: Unknown authorUnknown author
Permission: This 1932 issue of Short Wave Craft magazine would have the copyright renewed in 1960. Online page scans of the Catalog of Copyright Entries, published by the US Copyright Office can be found here. Search of the Renewals for Periodicals for 1959, 1960, and 1961 show no renewal entries for Short Wave Craft. Therefore the copyright was not renewed and it is in the public domain.
Usage Terms: Public domain
License: Public domain
Attribution Required?: No