WGBX-TV (channel 44), branded on-air as GBH 44 since 2020, is the secondary PBS member television station in Boston, Massachusetts, United States. Owned by the WGBH Educational Foundation, it is sister to Boston's primary PBS member station and company flagship WGBH-TV (channel 2), Springfield, Massachusetts-based PBS member WGBY-TV (channel 57, operated by New England Public Media), Class A Biz TV affiliate WFXZ-CD (channel 24) and public radio stations WGBH (89.7 FM) and WCRB (99.5 FM) in the Boston area, and WCAI radio (and satellites WZAI and WNAN) on Cape Cod. WGBX-TV, WGBH-TV and the WGBH and WCRB radio stations share studios on Guest Street in northwest Boston's Brighton neighborhood; WGBX-TV's transmitter is located on Cedar Street (southwest of I-95/MA 128) in Needham, Massachusetts, which is shared with WBZ-TV, WCVB-TV, WBTS-CD (which itself shares spectrum with WGBX) and WSBK-TV. The X in WGBX's callsign stands for "experimental", as WGBX (more primarily in the 1970s) was home to programming that was given a trial run on the lower-rated UHF signal before possibly moving onto the more-established WGBH-TV. Such Eastern Educational Network imports from the United Kingdom as Doctor Who were seen first or more frequently on WGBX, and one late 1970s local "nightclub"-style variety show, Club 44, proved popular enough to be moved over to WGBH and retitled The Club. The station airs PBS programs that are not aired by WGBH-TV as well as additional supplemental programming. Reruns of the previous night's programming either from WGBH-TV or from WGBX-TV itself also makes up part of channel 44's programming schedule. WGBX also carries most of the national digital subchannel networks (except for World Channel) which are managed by the WGBH Educational Foundation (along with an additional station, as described below); this enables WGBH to maintain a high-bitrate 1080i high definition picture resolution on its main channel 2 signal, with little loss in visual quality. History On December 11, 1963, the WGBH Educational Foundation applied for a construction permit to build a second station on channel 44; WGBX was approved on October 21, 1964. The station began broadcasting on September 25, 1967, and initially carried almost exclusively specialist programming, gradually turning into a second channel of educational and public programs. Since launching, its transmitter has been located in Needham (on a broadcast tower that is owned by CBS Corporation, and is used by some of the Boston market's commercial television stations, including CBS-owned WBZ-TV),