British use of high band.

[Adlershof]

Originally Posted by Colly0410

ind you the 405 lines VHF transmitters carried on broadcasting till the 1980's, the last ones shutting down on 31 Jan 1985, but almost everyone was then on 625 lines colour at UHF & no one noticed, there's a you tube video of it.

Indeed: The person, with her face never appearing in vision, waves into the camera and then turns off the 405 lines set, so the actual shut-down was not captured anymore


The BFBS problem was well known in Berlin back then. How did this UK-only system with sound on +5.996 MHz (that's how literature defines it) arise, this oddball in between B/G and D/K?

These armed forces transmitters survived much beyond the eighties. In the case of AFN the last ones disappeared only a few years ago, when anything else was already gone. Closure of the last BFBS TV transmitters in Germany was in 2008.

What disappeared much earlier were of course the Russian and French transmitters. They carried SECAM video in B/G, so no hassle with D/K or even the completely incompatible L norm here.

[Colly0410]

Originally Posted by Adlershof

Indeed:

The BFBS problem was well known in Berlin back then. How did this UK-only system with sound on +5.996 MHz (that's how literature defines it) arise, this oddball in between B/G and D/K?

.

Read in a TV mag that the reason Englands 625 system I chose +5.996 (originally +6 MHz) was so they could extend the video bandwidth up to 5.5 MHz as they didn't think the B/G bandwidth of 5 MHz was enough, & they didn't choose the 6 MHz video bandwidth of D/K as they wanted a vestigial sideband of -1.25 MHz for some reason. (D/K uses 0.75 MHz) Of course there could be a bit of protectionism thrown in as well so people couldn't just import European system B/G TV sets into England & they'd work OK. So they made the system just a little bit different to mess things up for Mr & Mrs Public. Just my cynical 10 cents worth..