Something involving Birmingham and Plymouth perhaps?
on UTV, and when there's no TX facilities at either Birmingham or Plymouth?
Re. the first capture with 'Television Test Signal Generator'. ISTR TV engineers having devices which generated various test signals like this in order to test/calibrate/identify faults with a particular set. Presumably it's a device like this generating it. Why would something like that ever be connected into the broadcast chain?
A CNAP is a switching centre on the BT network. I have seen these generators when we have been "miss-switched". Chances are there was a glitch on the BT network to UTV and this was automatically switched in.
BM/PY would indeed suggest Birmingham/Plymouth, but chances of it having anything to do with Plymouth are low - much more likely that there was a problem at Birmingham. Did anybody North of the border see anything similar?
If it was a hyphen between the abbreviations, I would expect it to be identifying a circuit from the place before the hyphen to the place after it, as in Birmingham to Plymouth.
However, as it's a slash, not a hyphen, I'd expect the whole abbreviation to be just one place, possibly Birmingham Perry Barr.
