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

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CO
commseng
That sounds correct to me (I think it was one of those bits of detail we were told at Wood Norton).
You can see how it makes sense to do it that way, back when TVC was being designed, although the introduction of colour made cable length even more critical. What the SPGs were I don't know, but hopefully someone else on here may well do.
MA
Markymark
bluecortina posted:
Didn’t the BBC have those modified dilithium crystal controlled NTSC SPG’s ? With cut cable lengths under the false floorIng of the donut to get every source timed to every destination? Hence why the building is circular to ‘lose’ the cables? I’m sure I have a paper on it somewhere.


Yep, that's my understanding too.

Didn't they run three sets of PSF1/3 for every video line, to future proof themselves thinking component RGB (and not as it turned out eventually (of course) YUV) would be the future for colour telly ?

(Thank god the component analogue era turned out to be mercifully short !)
CO
commseng
It may have been the thicker PSF 1/2?
MA
Markymark
commseng posted:
It may have been the thicker PSF 1/2?


Oh, I think you're right. I always feel I was born about 20 years too late.
MM
MMcG198
deejay posted:
I am just guessing here, but presumably because the suite worked to both networks it couldn’t therefore genlock to either (and I’m also guessing that the synchs for the two networks were separate and not necessarily locked to the same master synch). I have heard that each network control room had an OU Switch that put control of the network through to OUCON.


I had been told previously by BBC engineers that BBC One and BBC Two operated off the same syncs.

deejay posted:
It’s also well known that while a non synch cut from source to source was relatively invisible on television sets, VCRs were far more upset by them, so surviving recordings subsequently uploaded to YouTube make these cuts look far more violent than they actually were.


The sync issue between OU Con and the two network controls - when viewed live - was normally hardly noticeable at all. There are some examples online. One very nice one here, where they cut directly from the NC2 clock to the OU symbol in OU Con ( at 07:08 ):



And here's an example where the VHS tape made it look worse than it was ( at 25:38 ):

MM
MMcG198
Steve in Pudsey posted:
Were NC1 and 2 able to play out OU transmissions? I've seen some clips where it sounds like the same announcer doing the BBC 2 junction and the OU announcement.

I think the pres suites had Umatic for playing out emergency fillers?


Yes. Here's an example of where BBC One's weekend OU came from NC1 (probably due to a schedule change):



And here's an early morning OU transmission from OU Con, which breaks for the news via NC1. An odd fading out of the clock during the announcement. You can see the slight vision glitch when switching from OU Con to the clock in NC1.

https://tvark.org/?page=media&mediaid=115353
MM
MMcG198
Markymark posted:
In those dark days of the late 70s when BBC 2 would completely close down at 11:30 and not return until late afternoon, local clusters of transmitters were often kept on, by patching in pulse and bar, or linearity staircase at the primary regional transmitter. This would have been to perform maintenance on the transmitters, and also to set up new relay stations. Back then one new relay was built every week


It was a while after my post about p&b popping up again after close in that clip, that I realised I had seen this happen once or twice, live. It's such a long time ago - if I hadn't seen that clip or the resultant conversation on here, I would've totally forgotten about this.

All these fascinating little quirks of the analogue world.
SP
Steve in Pudsey
commseng posted:
What would be the reason for all the studios and pres areas having their own independent SPGs?
It sounds as if that would cause far more problems than it would solve?


Presumably because the ITV network was reconfigured several times a day. Before synchronizers the pres area had to sync with the incoming programme during the link which preceded it. (Hence why much of the presentation elements came from cameras, slide scanners etc which didn't object to adding or losing a few lines whilst on air rather than VT which most certainly did). Being able to do that without affecting every edit suite in the building had advantages.

Presumably studios had the same to facilitate locking to outside sources.

At the BBC it was the other way round, the incoming source had to adjust its syncs to match NC1/2. Some of the bigger regional centres had two pulse chains, one that was fixed and one that could change without notice. So edit suites would be on one chain and the studio on the other, which presumably meant that having to genlock the studio to contribute into Nationwide and then re genlock in other to opt out was less of a headache for any late edits.
SP
Steve in Pudsey
commseng posted:

In fact, as the next cog in the chain, our waveform monitor was locked to external syncs generated from Net 1. Net 2 locked to it exactly, so I am reasonably confident that was the case.
Next point north, Pebble Mill, also used to lock their SPG to the incoming Net 1 feed every morning, and would have used that for everything, and I can't imagine that any of the other studio centres with both networks going through them would have done anything different.


I gather that once Energis came along it was quite common for one network to be on its main path and the other to be on its reserve, so they could arrive in a region some distance apart.
MA
Markymark
Steve in Pudsey posted:
commseng posted:
What would be the reason for all the studios and pres areas having their own independent SPGs?
It sounds as if that would cause far more problems than it would solve?


Presumably because the ITV network was reconfigured several times a day. Before synchronizers the pres area had to sync with the incoming programme during the link which preceded it. (Hence why much of the presentation elements came from cameras, slide scanners etc which didn't object to adding or losing a few lines whilst on air rather than VT which most certainly did). Being able to do that without affecting every edit suite in the building had advantages.

Presumably studios had the same to facilitate locking to outside sources.

.


Yes. A prime example would have been LWT's World of Sport studio. They would have been even busier than pres swinging their SPG around constantly for the outside sources, and that would have kept all the ITV regional pres control rooms busy (inc LWT's own one) remaining in sync coming in and out of each of the ad breaks. Come the 80s, frame store syncs must have been top of list for every ITV chief engineer's budget submission!
TE
Technologist
Steve in Pudsey posted:
commseng posted:

In fact, as the next cog in the chain, our waveform monitor was locked to external syncs generated from Net 1. Net 2 locked to it exactly, so I am reasonably confident that was the case.
Next point north, Pebble Mill, also used to lock their SPG to the incoming Net 1 feed every morning, and would have used that for everything, and I can't imagine that any of the other studio centres with both networks going through them would have done anything different.


I gather that once Energis came along it was quite common for one network to be on its main path and the other to be on its reserve, so they could arrive in a region some distance apart.

There was no requirement for BBC one and BBC two to be co routed in the days when BT was the Telco pre Energis ....
going back to the TC cabling ...the " jumbo "14 cores of PSF1/2 was up to say 40ns difference across the cable .....
when doing TC5 for Sport i spliced in extra cables to get sub 5 ns ( probably only 2ns) spread before it hit the studio systems ... with 18 outside sources in it made commissioning and operating it a lot easier ....
Also the BBC did the colour timing by the destination doing a comparison of incoming colour sub carrier phase to its phase and then signaling to source to change its subcarrier phase .... a digital phase shifter ...
Of course this ruined SC/H which became fashionable until SDI got rid of subcarrier all together... and had line syncs everywhere so timing mattered a lot less
in TC5 we were timing down to under a degree ...
BL
bluecortina
Steve in Pudsey posted:
commseng posted:
What would be the reason for all the studios and pres areas having their own independent SPGs?
It sounds as if that would cause far more problems than it would solve?


Presumably because the ITV network was reconfigured several times a day. Before synchronizers the pres area had to sync with the incoming programme during the link which preceded it. (Hence why much of the presentation elements came from cameras, slide scanners etc which didn't object to adding or losing a few lines whilst on air rather than VT which most certainly did). Being able to do that without affecting every edit suite in the building had advantages.

Presumably studios had the same to facilitate locking to outside sources.

At the BBC it was the other way round, the incoming source had to adjust its syncs to match NC1/2. Some of the bigger regional centres had two pulse chains, one that was fixed and one that could change without notice. So edit suites would be on one chain and the studio on the other, which presumably meant that having to genlock the studio to contribute into Nationwide and then re genlock in other to opt out was less of a headache for any late edits.


That sounds like a recipe for getting into pulse howl round. As a source, genlocking to a destination is fraught with ‘danger’ as you can end up looking at yourself. I don’t know of any ITV Station ever doing that. I thought the reason the BBC devised Natlock was to eliminate genlocking? But perhaps the BBC requirements changed over the years?

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