WGBX's current digital transmitter shares the master antenna at the very top of the tower with the commercial stations. The now-defunct analog signal maintained a separate antenna on a lower portion of the tower that was shared with WGBH's digital transmitter. WGBX shut down its analog signal, over UHF channel 44, on April 23, 2009. The station's digital signal continued to be broadcast on its pre-transition UHF channel 43. Through the use of PSIP digital television receivers display the station's virtual channel as its former UHF analog channel 44. World Channel moved from digital subchannel 44.2 to 2.2 in the spring of 2012, replacing WGBH's standard definition simulcast. On January 16, 2017, WGBX switched its DT4 subchannel from a locally programmed loop of children's programming (which looped twice a day) to the relaunched national PBS Kids channel. On January 18, 2018, WGBX began a channel share with Nashua, New Hampshire-licensed WYCN-CD (channel 15, now WBTS-CD), which was acquired by the NBC Owned Television Stations subsidiary of NBCUniversal. Despite WBTS-CD's low-power status, WGBX's transmitter acts as a full-market relay of WBTS-CD, an NBC O&O station, along with its Cozi TV subchannel; WGBX's multiplexer was then upgraded to handle WGBX's existing HD channel and two SD channels, along with WBTS-CD's HD channel and one subchannel as a result of the channel share. In 2019, with WGBH moving to VHF 5, both station's channel maps were adapted, with WGBH handling both the 2.1 and 44.1 HD signals, and WGBX mainly carrying standard definition subchannels in order to provide appropriate bandwidth to WYCN-CD, which itself had its calls changed to WBTS-CD in the same period of time. This is equivalent to the channel distribution plan used by Twin Cities PBS in Minneapolis–Saint Paul, which divides its subchannels among two existing stations (though all channels map to channel 2 rather than the second station's channel 17). Technical information Subchannels The station's digital signal is multiplexed. Note that WGBX-DT1 actually transmits as WGBH's second subchannel to provide a full-quality high definition signal for that station: See also Channel 32 digital TV stations in the United States Channel 44 virtual TV stations in the United States List of television stations in Massachusetts List of United States stations available in Canada References External links PBS member stations Television channels and stations established in 1967 1967 establishments in Massachusetts GBX-TV WGBH Educational Foundation