For those in the UK, We in North America could occasionally receive BBC1 from transmitters across the British Aisles when Solar activity was high. The Band-1 transmissions were roughly between 41 and 45 MHZ. Audio was AM or amplitude modulation as well as was the video which was 405-lines and monochrome.
We could receive the signals during Winter and only when it was daylight in both places. The Band-1 transmissions had been active from the 1930's until 1986 except for World War II when they were switched off to save money and remove a perfect beacon source for bombers to use for guidance. The radio frequencies between 41 and 45 MHZ are used in the Americas for emergency services and business two-way radio so when the video signal was strong, folks using two-way radios in that range had loads of whistles and buzzes to jam their transmissions. People in the UK who may have lived in weak signal areas probably saw lots of video disturbances from signals in the Americas so while the unusual reception was interesting for us radio enthusiasts, it really did none of the proper users any good at all. That's partly why the BBC discontinued those transmissions in 1986 and we in North America went digital in 2012. I listened to the sound of numerous transmitters in Britain and France which had a similar system on slightly different frequencies around 1970 and again around 1980-82 . I remember hearing some of our emergency services trying to talk over the video buzz and not doing too well. Sorry for the extremely off-topic post, but I thought some might find this interesting. Martin