BBC teletext service, Ceefax, was introduced, created initially to provide subtitling, but developed into a news and information service. In 1978, BBC staff went on strike just before the Christmas of that year, thus blocking out the transmission of both channels and amalgamating all four radio stations into one. Since the deregulation of the UK television and radio market in the 1980s, the BBC has faced increased competition from the commercial sector (and from the advertiser-funded public service broadcaster Channel 4), especially on satellite television, cable television, and digital television services. In the late 1980s, the BBC began a process of
BBC World Service 05:20am on BBC Radio 4 FM & DAB. It has always been in mono on its own DAB channel with a bit rate of just 64 kbit/s. BBC World Service can also be heard on BBC Radio Wales from 01:00am until 05:30am on MW and FM stereo. In the 1990s, the BBC purchased and constructed large medium wave and FM networks in the former Soviet bloc, particularly the Czech (BBC Czech Section), Slovak Republics (BBC Slovak Section), Poland (BBC Polish Section) (where it was a national network) and Russia (BBC Russian Service). It had built up a strong audience during