Channel 4 pre-1993 regional opt outs

Indeed, that was the whole point of using IDENT and CATS in the first place !

Red phone? I’m assuming that that was for emergencies?

No - red phone wasn't for emergencies per sé - but a quick (and routine) way for the nominated network contractor to contact all the other control rooms and some offices. I'm sure others with better knowledge on the subject will be far better placed to elaborate.

However, my understanding (in brief) is that pre-consolidation, at any given time of the day one ITV Franchise holder was 'nominated contractor' and would be responsible for co-ordinating the presentation of networked programmes. It varied throughout ITV's history of course, but examples are ATV/Central for Schools programmes (before they moved to Channel 4) and Thames/LWT for peak/weekends. I think I read that Granada may have been the nominated contractor for Daytime up until CITV, which was Central's gig.

When the schedules for ITV were regionally very diverse, it was often the case that the lines between stations were switched during breaks.

The red phone network was always switched so that the nominated contractor could initiate calls to inform other stations of changes to the schedule, breakdowns, amendments etc.

I see. I can't help but think of times when breaking news has caused such a change eg LWT when Tommy Cooper passed away live.

The mechanics of that were discussed in here a few years ago, I can't find the thread, only ones that make a passing reference, perhaps someone with better search skills than me.......?

Here...

https://tvforum.uk/tvhome/tommy-coopers-death-30643/

That's the kind of thread that brings out the best and worst in people. I was 6 when Tommy Cooper died and remember his face in close up and a hand being seen. Didn't know it was Tarbuck's.

Yes, I found that one, but it's not the one I'm thinking about. I found a thread I started in 2014, it's not that one either. I've got a feeling it was an off topic drift thread from something else, but it was in the last 2 or 3 years I think ?

Ugh. That thread just reminds me of clicking on the link and watching it without fully realising the effect it would have afterwards. If that ever gets uploaded again, don't watch it. It's not worth it.

I've just been having a clear out, and found an article from an 1982 edition of International Broadcast Engineer.
It takes about a Logica Teletext System to relay information and cues to the the ITV companies. It used Line 21 and was stripped out leaving the ITV companies before hitting the transmitters. Oracle Teletext back then was Lines 15-18.

Quote:
'Should an ITV company wish to operate its commercial machines automatically, C4 also transmits four distinct cues on the line 21 system, which can be assigned to any such function. In addition this Logica system also provides an electronic mail service from Charlotte St to the ITV stations, feeding C4 schedules and other data to hard-copy printers at regional studios

Edit:

Found more, a 1988 article.

Quote:
'In late 1987, they added a Sony Betacart machine for the 09:30 to 12:00 Schools Progs, which are recorded by Central TV, complete with announcements on a separate cartridge. The machine just needs loading, and is controlled by CATS, although a 1 inch copy is made the night before and run in parallel as a back up.

Edit:

Fill yer boots

https://www.dropbox.com/s/7alhtva7f31hjbb/C4_scans.pdf?dl=0

Interesting thanks. As I recall the teletext signal was also inverted to further prevent accidental unauthorised de-coding. I’m trying to remember how it was stripped off before leaving the station, I think line 21 was one of the IBA ITS lines and so it might have been simply replaced by the inserters just before it left the building?

Some small detail on the IDENT screen (captioned as CATS in the article). The LH column is real time, the RH column is the duration of each event. Events chuntered up the screen to the top line as they became sequentially active - then that event simply counted down for its duration. In the capture it looks like a 3.40 end break counting down towards its end. Different types of events had different screen colours to aid easy at a glance viewing.

I've just taken a look in my IBA COP document, ITS was line 19 and 20 (same for the Beeb too I'm sure)
I can remember seeing Presfax data on BBC1/2 on line 21, it would vanish during regional opts (at least here in the south).
I can't remember whether on the rare occasion I saw C4 being fed directly to Rowridge, whether the IDNET data was present (Need that DeLorean mentioned up thread )