Westinghouse "Tomato Can" microphone from station KDKA. Adaptation of telephone transmitter in suitable mounting, incorporates acoustical equalizer and other minor refinements. Same technical limitations as Cat. No. 311,443. This instrument is the actual instrument used in broadcast of press bulletins of Harding-Cox election returns Nov. 2, 1920, an event sometimes considered as the beginning of broadcasting. Brass can painted black, wire gauze at one end.