for Morse code transmissions. In April 1917, due to the entrance of the United States into World War One, all civilian radio stations were ordered silenced, including 8XK. During the war Westinghouse was awarded government contracts related to developing radio technology, and Conrad worked on improvements to radio equipment (SCR-69 transmitter and SCR-70 receiver) for the Army Signal Corps. In addition to Morse code, this development work included radiotelephone transmissions, using the recently developed capabilities of vacuum-tube transmitters. In conjunction with his wartime work Conrad was authorized to operate a radio transmitter from his home, using the call sign 3WE, for communication with a second station located at the Westinghouse plant in East Pittsburgh. He also produced a wind-driven electrical generator, attached to a plane's wing, for powering a radio transmitter. Effective October 1, 1919, the ban on civilian radio stations was lifted. Although his station would not be formally relicensed until January 21, 1921, Conrad resumed experimenting, again using the 8XK callsign, and now also testing vacuum-tube radiotelephone equipment. He was responsible for one of the country's first post-war radio broadcasts, when, on the evening of October 17, 1919, he entertained local amateurs with selections from phonograph records. This was the start of a series of test broadcasts, and the novelty of the entertainment proved popular with his audience. Responding to their interest, Conrad adopted a semi-regular schedule, primarily consisting of two hours on Saturday and also Wednesday nights. (The broadcasts weren't universally appreciated, as his wife later reported that he also "used to get phone calls at all hours of the day and night telling him to get off the air".) Most of these early broadcasts consisted of music, provided from Conrad's record collection. After he exhausted this resource, he struck a deal with the local Brunswick Shop: in exchange for the store supplying him with recently released records, he would provide on-air acknowledgements. (The son of the Brunswick Shop's owner had been assisting Conrad). Conrad's sons and niece were talented musicians and helped provide the entertainment. He also ran a telephone line from his home's music room to the transmitter in the garage, so performers could use the family piano. On June 26, 1920, a special concert was broadcast for the patients at the Tuberculosis League Hospital. Conrad also continued to conduct experimental radio work. In the summer of 1920, the American Radio Relay League, in conjunction