W1WX was Boston's first television (after W1XAY). It began broadcasting in April of 1929, and was owned by Shortwave and Television Laboratory, Inc. Initially it broadcast on 2120 kHz with 100 watts of power. It broadcast 48 line pictures, 15 frames per second. In September of 1930 it moved to 2.1-2.2 mHz, with 500 watts of power, and changed to 60 lines, 20 frames per second. In December of the same year it changed its call sign to W1XAV. In 1934 the station went off the air.

Shortwave and Television Laboratory, Inc., was founded by A. M. "Vic" Morgan, Butler Perry, and Hollis Baird.

In 1930 W1XAV Boston broadcast a video portion of a CBS Radio orchestra program, The Fox Trappers,  sponsored by I. J. Fox Furriers. Included was what may have been the first television commercial. FRC (Federal Radio Commission, now the FCC) regulations prohibited commercials on television, since all stations were at that time experimental.