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Did the BBC 2 Test Card ever have the 1986 "TWO" ident?

GE
thegeek Founding member London London
I wonder when the BBC stopped using Test Card G? I can't remember ever seeing it in the late 80s and early 90s

It randomly turned up on BBC Parliament one Saturday afternoon in 2003 as I reported here: https://tvforum.uk/tvhome/bbc-parliament-6210

Remember that in 2003, BBC Parliament was originated from Millbank Studios, which was a subsidiary of Granada (by way of Yorkshire TV) - it's possible they inherited kit from there.
JA
james-2001 Central (East) East Midlands Today
A look on Google and I found an off-screen photo of the electronic TCF with the short lived basic captioning:

https://flic.kr/p/HGRFMc
MA
Matt7924 Central (West) Midlands Today

That looks like the one. I remember seeing it myself on youTube a few years ago, but someone must have managed to see it when it was first shown. I know the MHP site hasn't been updated for years.

I wonder when the BBC stopped using Test Card G? I can't remember ever seeing it in the late 80s and early 90s


Were the BBC nations supplied with electronic TCF generators? If so there was probably little need for G from that point, either in London, or in the nations?

LWT used to use a vanilla PM5544 after closedown in the 80s, I don't think any other ITV company did, it was either colour bars or black?


I had heard about LWT using a PM5544, I'm not sure why they did this, rather than handing over to the IBA to show ETP1. It seems that not all ITV companies bothered with the ETP1 after closedown, as you mentioned colour bars or a black screen.
MA
Markymark Meridian (Thames Valley) South Today
That looks like the one. I remember seeing it myself on youTube a few years ago, but someone must have managed to see it when it was first shown. I know the MHP site hasn't been updated for years.

I wonder when the BBC stopped using Test Card G? I can't remember ever seeing it in the late 80s and early 90s


Were the BBC nations supplied with electronic TCF generators? If so there was probably little need for G from that point, either in London, or in the nations?

LWT used to use a vanilla PM5544 after closedown in the 80s, I don't think any other ITV company did, it was either colour bars or black?


I had heard about LWT using a PM5544, I'm not sure why they did this, rather than handing over to the IBA to show ETP1. It seems that not all ITV companies bothered with the ETP1 after closedown, as you mentioned colour bars or a black screen.


After close down the black or bars was just a holding signal before they pulled the U links to remove syncs to initiate the transmitters to automatically shut down.

The IBA normally woke up the transmitters with local ETP1 (at the transmitters) before switching the local ITV company back into circuit.

None of the ITV companies had their own ETP1, only C4 and S4C
SC
Si-Co Tyne Tees Look North (North East)
Seeing as we are talking about transmitter switch ons and switch offs, a couple of back to basics questions:

At the start and end of each day, did each main transmitter have to be manually switched on and off, either from staff on-site or elsewhere? What about relay stations? Back in the early 80s, on BBC One, I noticed that there would be a period of black or some sort of test tone/bars on start up before Pages from Ceefax began about 8.30.This was when watching from Pontop Pike, the main transmitter for our area. However, when watching from Fenham, one of the relays, often this was completely off air until about 8.45 and “crashed” straight into the Ceefax pages.
CEEFAX SUBTITLES BEGIN SHORTLY
MA
Markymark Meridian (Thames Valley) South Today
Si-Co posted:
Seeing as we are talking about transmitter switch ons and switch offs, a couple of back to basics questions:

At the start and end of each day, did each main transmitter have to be manually switched on and off, either from staff on-site or elsewhere? What about relay stations? Back in the early 80s, on BBC One, I noticed that there would be a period of black or some sort of test tone/bars on start up before Pages from Ceefax began about 8.30.This was when watching from Pontop Pike, the main transmitter for our area. However, when watching from Fenham, one of the relays, often this was completely off air until about 8.45 and “crashed” straight into the Ceefax pages.


Main stations switched on when they detected incoming sync pulses. Secondary main stations fed off air were the same, they detected when the feed signal popped up, and switched on. Relay stations were the same again, only they couldn't detect sync pulses, because they were dumb terminals, so they switched back on on detection of incoming RF from their parent. There were anti hysteresis measures built into the system to prevent power up and power down reacting too quickly, so it look about 20-30 mins for some remote stations on the end of long rebroadcast chains to come on compared with the main transmitter for each region.

Switch off was the reverse process once syncs had been removed, but syncs had to be continuously missing for 2-3 mins before the first station in the chain shut down.
SC
Si-Co Tyne Tees Look North (North East)
Thanks Mark. So where would the initial sync pulses to “wake up” the transmitters be generated from, in each station’s case?
CEEFAX SUBTITLES BEGIN SHORTLY
SP
Steve in Pudsey Yorkshire Look North (Yorkshire)
On the incoming feed coming from London, or picked up from another transmitter via RBS, they are part of the video feed. According to a discussion I'm reading elsewhere, it was sync pulses *and* sound that were required to start the transmitters up. And presumably the VBI ident to verify that the signal was legitimate.
Write that down in your copybook now.
JA
james-2001 Central (East) East Midlands Today
Watching VHS recordings of closedowns, the point where the syncs were removed is very obvious because of how it makes the picture bounce all over the place.
TE
Technologist London London
On the incoming feed coming from London, or picked up from another transmitter via RBS, they are part of the video feed. According to a discussion I'm reading elsewhere, it was sync pulses *and* sound that were required to start the transmitters up. And presumably the VBI ident to verify that the signal was legitimate.


You unplugged the input to the [DC] Sound in Syncs encoders ......
they put out line syncs only ..so there was a signal on the line ..
But the main station would see no field syncs and start to turn off.
Start up in the morning put them in and as has been said the stations would start to power up .... nothing was that fast ....
and yes there were means in the VBI to ident the source so the transmitter would accept the signal ...... very useful for RBS at main stations
as well as The normal RBL at main relays ..
and it told Douglas to take Manchester not Carlisle / Newcastle for the regional opt ... Caldbeck was a better signal than Winter Hill so was used for Network programmes
Inspector Sands, Steve in Pudsey and Si-Co gave kudos
MA
Markymark Meridian (Thames Valley) South Today
On the incoming feed coming from London, or picked up from another transmitter via RBS, they are part of the video feed. According to a discussion I'm reading elsewhere, it was sync pulses *and* sound that were required to start the transmitters up. And presumably the VBI ident to verify that the signal was legitimate.


For ITV of course there were no Sound in Syncs used until 1989 and NICAM, so yes absence of analogue audio may well have also been required. As Mr T points out for the Beeb (and C4) the audio died with the SiS going. I don't think the IBA used VBI identing to the same extent as the BBC

I'm not sure the really tiny relays (just a few watts) ever actually switched off. Back then it was impossible to remote control them, or know whether they were even working. The BBC and IBA had a network of trusted individuals each in the service area of the relays who would report in if they noticed any problems. Since DSO all relays have a data link back to Arqiva's ops room at Emley. Either an ADSL line, or in the case of very remote realys a VSAT link
Last edited by Markymark on 1 August 2020 8:52am
ST
Stuart West Country (West) Spotlight
I'm sure this will sound completely irrational, but when I was very young the Test Card used to scare me somewhat. Not because of the clown, but because from my perspective I saw a "green skull, with 2 yellow eyes and a pink tongue" staring up at the girl. Shocked
*

Perhaps I had a disturbed childhood. Confused

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