Classic ITN presentation Take 3

Quantel wanted to stop making the 1751s years before they were actually able to, as they kept getting orders for them (including the Quantel Link deal to supply the BBC with their Type VIII trucks). Sourcing PSUs got tricky ISTR. They had the major advantage of having a GIGO mode (Garbage In Garbage Out) which is exactly what you want on a dodgy analogue RF camera link, not a freeze...

Noisy fans ISTR...

The very early LDK5s delivered stonkingly good pictures for a tubed camera of that era. The first models had very optimised aperture correction circuits that really delivered clean, sharp pictures, but avoided looking 'French'...

They also had the huge advantage of being triax...

I don't know the lineage of the LDK5, I recall seeing not that long ago an edition of the Nana Mouskouri Show which I think was dated 1967 on BBC2. Putting aside the fact the pictures were obviously sourced in 625 they were absolutely tip top, stonkingly good! Unbelievable!

I sort of presumed they were being shot on PetoScott cameras which again I also sort of presumed fed into the Philips range of cameras - any thoughts?

I think I remember the PSU's, a long pcb about 3 inches wide with outsourced (ie bought in) convertor modules?

What I do remember is that it had two operational 'What to do if the input signal fails or is crappy'. One was to permanently freeze the output signal to be the last known good frame, but wasn't up to much as the freeze was like you had picked the picture up with a cloth and were lightly polishing it - not a good description! I think of it as the frozen picture gently oscillating in a gentle circular fashion like the motion you would get if you were polishing a window plane. The other mode as I recall was to 'go to black' for the duration of the crappy signal, but I think it was oversensitive and was not used. I think I may not be remembering that too correctly?

Edit: Yes - noisy fans and likely to fail over time with attendant problems - one for 'routine maintenance". I recall now there were some 9 bit Marconi 1U syncs - there were excellent, really good. Perhaps they benefitted from being a bit late on the scene.

Edit 2. Quantel wouldn't do a maintenance course on the 1751 (for us anyway), we assumed they were paranoid about their circuits although they all came with a full maintenance manual including circuit diagrams. We had a local chap who was superb at designing and running courses, so he sort of reverse engineered it from a theory of operation point of view and did the course for us. Very clever and nice chap too.

Ha ha! In reality the Peto Scott cameras didn't really exist. It was a badge engineering job really.

The Peto Scott cameras were effectively Phiips LDK3s, but because they were bought from Peto Scott they were 'British'... I'm sure there were BBC modifications and there were both PC60 and PC80 models - but AIUI they were effectively LDK3s. SVT in Sweden used their LDK3s well into the 80s...

They generated nice pictures - but had hefty (dual in some cases?) multicore cables.

Have a feeling the first colour handhelds the BBC had - the Philips Minicam (developed by Philips Norelco in the US ISTR) - were re-badged as Pye for the same reason.

I wonder if the BBC had modified 1751s then? The most important thing was that they passed through synchronised garbage! It's why they were used for RF cameras (and thus installed in most larger OB trucks that could be expected to use RF cams)

Maybe, it was all a long time ago and I was never involved with crappy pictures!!

NB. Have altered my original post above with regard maintenance courses on it (or not as the case may be).

First ever time I saw colour TV was 67 ish, and it was Nana Mouskouri on BBC 2 on a telly in a shop window
in the middle of Basingstoke. We were in the car, and stopped at the traffic lights. We were so transfixed by
it, my father failed to notice the lights change green, and a policeman tapped on the window !

Synchronisers:-
What were the Beeb using in Net 2 in 1985 ? (Ironic lyric being sung as the feed failed !)

https://www.youtube.com/watch?v=VslJEUpSnXk

Not sure. I know Marconi synchronisers were in use in some areas of the BBC at one point. Quantel and Questech models were normal in OB trucks.

Also not sure if Network had their own synchronisers or if OBs were synchronised up-stream, so they arrived to Pres synchronous, like studios?

I should probably re-phrase this a bit. Philips Plumbicon cameras were effectively a response that Philips Norelco in the US took to the US dominance of RCA in the camera marketplace. As RCA and NBC were commercially linked, CBS in particular wanted a decent camera from someone other than RCA (as they didn't want to give money to their rivals...)

CBS therefore worked with Philips Norelco (i.e. North American Philips) to develop the PC-60 camera.

In the UK the Philips Norelco PC-60 was re-badged as a Peto Scott PC-60 (as the BBC always wanted to 'Buy British' at that time, in Europe I think it was re-badged as the LDK-1... There was also a PC-70 and a PC-80. One of these became the LDK-3.

Good article in Dutch here : https://www.omroepmuseum.be/index.php/geschiedenis-radio-tv/televisie/24-toestellen/televisie/studiocamera-s/36-de-camera-die-een-revolutie-veroorzaakte

They mention that the input from the BBC and CBS helped the cameras properly evolve.

(From memory the LDK-1/PC-60 needed two multicores, the LDK-3/PC-70 and PC-80 only needed one?)

That particular clip was a total power failure for the OB trucks at Wembley, so I think the frozen image was probably a sync at TVC. I was listening to the audio on Radio 1/2 FM, that died too, accompanied by a huge thump of electrolytic capacitors discharging !

'House' power at Wembley is still a problem today I'm told, (and that's despite the total stadium rebuild 15 years ago !). No OB company trusts it there, and they use their own gennies (much like they do anywhere else quite honestly)

The Radio 1 audio of that clip used to be on YouTube but it isn't now! Lots of silence followed by a jingle and then the DJ (can't remember who) reading out the phone numbers to donate.