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robertclark1251,424 posts since 13 Jan 2009
STV Central Reporting Scotland
That YTV one was interesting for the LWT colour bars. I think that's been on this thread before, but I would suggest that either YTV was showing it locally, and British Telecom, trying to establish the feed again routed things to LWT by mistake, or LWT was networking it.

Interesting they went to the Independent television breakdown caption, as opposed to a YTV caption. I always thought that it had to be black sent to the transmitter for 30 seconds before the transmitter took over. That wasn't 30 seconds!
Inspector Sands13,817 posts since 25 Aug 2004
That YTV one was interesting for the LWT colour bars. I think that's been on this thread before, but I would suggest that either YTV was showing it locally, and British Telecom, trying to establish the feed again routed things to LWT by mistake, or LWT was networking it.

Interesting they went to the Independent television breakdown caption, as opposed to a YTV caption. I always thought that it had to be black sent to the transmitter for 30 seconds before the transmitter took over. That wasn't 30 seconds!

I would have thought the caption at the transmitter would appear when there's a lack of video rather than black video. 30 seconds of that seems a long time. It looks like the line that went down was between YTV and the transmitter(s)*.


The circuit out of LWT was either a mistake, or some sort of work around, with the output going down to LWT and then back up to the transmitters.


*of which they had more than one, so either they lost everything out of their building or everyone saw the captions even if they weren't watching the transmitter that went faulty (which presumably is the one they can watch off air at Leeds - Emley Moor?)
Markymark7,060 posts since 13 Dec 2004
Meridian (North) South Today

I would have thought the caption at the transmitter would appear when there's a lack of video rather than black video. 30 seconds of that seems a long time.


Here's a You Tube video of the night LWT's pres mixer died (We've discussed it in here too, Bluecortina gave us a lot of detail).

You can see the video and syncs fail, and then 30 seconds later the IBA caption cut in (note the audio was unaffected). Then it looks as if LWT patched the VTR directly to Tx to restore things, but then we end up with the end cap until the next event is manually patched

https://www.youtube.com/watch?v=yODNh-ky-Fc
commseng249 posts since 8 Dec 2016
London London
Was the output line to CP on the MCR matrix, or was it a manual overplugging required?
I assume the audio to CP was an analogue line rather than SIS in 1981, which would have made it difficult to keep both correct when there was a major panic on.
1
LewisS gave kudos
Steve in Pudsey10,249 posts since 4 Jan 2003
Yorkshire Look North (Yorkshire)
That YTV one was interesting for the LWT colour bars. I think that's been on this thread before, but I would suggest that either YTV was showing it locally, and British Telecom, trying to establish the feed again routed things to LWT by mistake, or LWT was networking it.

Interesting they went to the Independent television breakdown caption, as opposed to a YTV caption. I always thought that it had to be black sent to the transmitter for 30 seconds before the transmitter took over. That wasn't 30 seconds!

I would have thought the caption at the transmitter would appear when there's a lack of video rather than black video. 30 seconds of that seems a long time. It looks like the line that went down was between YTV and the transmitter(s)*.


The circuit out of LWT was either a mistake, or some sort of work around, with the output going down to LWT and then back up to the transmitters.


*of which they had more than one, so either they lost everything out of their building or everyone saw the captions even if they weren't watching the transmitter that went faulty (which presumably is the one they can watch off air at Leeds - Emley Moor?)

I think the 30 seconds of black thing applied when the transmitters were fully staffed, if there was 30 seconds of black the IBA would take back control and put up an apology - usually applied around strikes etc.

I suspect the YTV example was the circuit from YTV to the transmitters failing. My assumption was that the LWT bars was the incoming network feed to YTV being patched directly to the transmitters in error.
Write that down in your copybook now.
Markymark7,060 posts since 13 Dec 2004
Meridian (North) South Today
Was the output line to CP on the MCR matrix, or was it a manual overplugging required?
I assume the audio to CP was an analogue line rather than SIS in 1981, which would have made it difficult to keep both correct when there was a major panic on.


I think ( and I remember seeing it all happen on the night) it was over plugging because there were periods of no sync ( the IBA caption made multiple appearances) It also affected LWT’s output to the ITV network ( which is how I knew something had failed, I was watching on Southern when PYCR failed, so I switched over to LWT to see what was going on) As I say bluecortina gave us some details a few months ago, if someone can dig up the thread again ?
commseng249 posts since 8 Dec 2016
London London
In hindsight to have one vision mixer doing both the network feed and local output wasn't very resiliant.
I can understand why the later solution was built around two desks.
It must have been a fun night for all those involved.
bluecortina863 posts since 26 Jul 2012
In hindsight to have one vision mixer doing both the network feed and local output wasn't very resiliant.
I can understand why the later solution was built around two desks.
It must have been a fun night for all those involved.


The YTV fault looks like a simple switching error or fault at the Leeds BT switching centre.

LWT. Complete failure of the CDL transmission desk and integrated MCR switching desk. Some great people on that night, cool heads among the engineers and presentation staff. Subsequent rebuild in the early 80’s was a changeover to custom built GV kit, but, the main network switcher feeding KRS3 remained on CDL - parts of which were retained to give extra resilience and the network switchers liked the ‘feel’ of the faders on the CDL panel.
Last edited by bluecortina on 12 July 2019 12:25pm