W6JDI-TV

Background

W6JDI-TV was the call sign of an unlicensed television broadcast in San Francisco by an amateur radio enthusiast named Clarence Wolfe Jr., who, in 1948, created his own television station using home made equipment. In 1932, Wolfe received a HAM radio license, he used the callsign W6JDI. He worked on W6JDI-TV for several years, despite never receiving a television broadcast license, which had been first issued in the United States in 1941. His channel has been nicknamed "HAM TV" and "Wolfe TV", though it only ever went by it's callsign. The channel only broadcast one still image, which Wolfe used to test signal strength and reception by receiving feedback from fellow HAM users. In an August of 1949 issue of Popular Science magazine, it is mentioned that Wolfe had planned to broadcast live content, however, evidence suggests he never managed to achieve this.

Test Card (1948-1949)

Visuals: A single still image of a woman with brown hair, who became known as "Gwendolyn".

Technique: Live-action photograph.

Audio: None.

Availability: Images sourced from August 1949 issue of Popular Science magazine and California Historical Radio Society.

Legacy: This test card seems to be a precursor of BBC's Test Card F, which also used a live-action photograph for its visuals.