[Si-Co]

This example from late-1981 shows the blue caption kicking in less than 30 seconds after loss of video.

www.youtube.com 

Interesting example. Again from memory the apology card would kick in for continuous loss of video too. Again I thought is was around 2 mins but your example seems to confirm it was shorter. If you were transmitting anything with a long section of black or silence you advised the transmitter in advance of the tx so that the automatic detection system could be bypassed. I vaguely recall playing out the war film ‘The Longest day’ and the opening scene consisted of a fair bit of black with the somewhat famous V for Victory sound track only (there are different opening versions of the film so don’t bother to Google). When I was showing it to Pres a short while before transmission I advised them of the long section of black and it wasn’t a fault on my vt machine!

The YouTube clip pointed to captures a somewhat infamous night at LWT transmission. The complete presentation and networking ‘desks’ failed for a period and there was frantic over-patching going on to try and keep the show on the road - networking bring a primary task. I would presume the other ITV companies taking these network transmissions would have put out local apology captions. Two completely local separate tx paths from Kent House to Crystal Palace but neither any good if the common sending point has fallen over, both the local Pres desk and network equipment shared common CDL frames and had gone faulty. Very, very cool heads prevailed.

I remember seeing that fault on Tyne Tees. They did put up their own slide (the holding slide for PYCR), and from memory they lost the sound too, or opted not to continue in sound only. They returned to the programme quite a few seconds later than LWT did, just as Bruce was saying good night. So TTT viewers had no idea if the couple had won the star prize or not. Sometimes the announcer would tell viewers the outcome of the game in a later junction - this definitely happened one Sunday teatime when TTT lost Bullseye and were unable to return to the programme.