The digital Nicam 728 transmission standard, which conveyed stereo to most of the UK in the 1990s, presented an alternative. The bitstream was encoded in the syncs of the baseband video signal; modulated on to a subcarrier above the video. This was developed by TV-am plc in 1992-93 at the time they operated a studio at the National Museum of Photography, Film and Television in Bradford. The system was used by several UK broadcasters.