80th Anniversary of BBC TV preview

[Nick]

I really enjoyed that - nice to see you dressed up for your cameo, Jeffrey  

It was impressive - considering that there seemed to be only 6 weeks to get everything together, I thought it was champion. Didn't miss the technical content at all - it's a narrative, not a lecture.

[ppppenguin]

To do 240 lines the Baird company had to run the scanning disks in a vacuum. I don't know if it was air currents that affected the running or just that the disc wasn't as flat and rigid as it might have been.

[`FRANK.C]

I seen the repeat on BBC4 last night, I enjoyed it. I know very little about the Baird system and the show brought home how little I knew. I had always assumed that the sensor was behind the spinning disc and not the light . The light proof box for the presenter was an eye opener, what a difficult job to present under those conditions.
It would have been nice if the M-EMI studio was shown in operation as well so we could compare, I suspect it would be like chalk and cheese.

well done to Jeffery, it always makes a program more interesting  when there is someone in it we know.

Frank

[ppppenguin]

The original M-EMI studio would have been recognisable as a modern one. A room with lighting, scenery and cameras being pushed around. OK, the kit was much cruder back then but it was still cameras with cables snaking across the floor. Paul's camera, using an early postwar iconoscope, is the nearest thing in existence to the original Emitron cameras. Original tube but all modern electronics.

[AlanBeckett]

OK, I'll be the Little Boy who doesn't believe the Kings New Clothes.

I thought it was pathetic, hopeless, abject even, especially as it was the BBC and the Channel it was on.

It had all the ingredients of a 'Modern' TV Programme:-
1. You need a job lot of attractive 'Presenters'. They must have the ability to rush about, be filmed in odd locations and pretend that the Camerman etc aren't already there, memorise the Subject matter and be able to regurgitate it in a manner which sounds as though they know what they're talking about and smile a lot. Knowledge of the Subject is not a requirement.
2. You need to generate artificial 'Tension' - 'We've only got 6 Weeks to get it done'.
3. You need a strong element of British Amateurism - the Disk and its Drive were hopeless. I could do better than that in 6 Days in my Garage with the Junk I have available, let alone with 6 Weeks and a no doubt generous Budget to go at.
4. You need to present it in a manner which will catch the attention of a bored 10-year-old.
5. It was too long.

Like Dick above, I would have preferred a proper Documentary

Alan

[Raditechman]

I had hoped to see a recreation of the original opening programme, as similar to the original as possible. Shown in the correct aspect ratio.
Seems they hired some artists to re-enact the show, but we only saw snippets. They said the juggler/contortionist act was cut from the original show yet still booked a similar act for the re-run.
Nice to see Jeffery even though it was an uncredited role.

John

[ppppenguin]

Alan, I think you're rather demeaning the main presenters. Both are highly qualified engineers, albeit in their own fields. Danielle's projects include the RF systems for the Square Kilometre Array radio telescope. She got her professorship at age 38. She also happens to be very photogenic.

I saw the jugglers/contortionists do their whole performance at Hornsey Town Hall. They were superb. We only see snippets in the programme. Likewise the tap dancer.

The main hall where the performers were filmed was £$%^& freezing. Almost to the point of seeing breath condense. The singer and musicians got out of there as fast as possible after the performance. It's also why you see some people in warm jackets and scarves. The foyer, where you see the TV song being rehearsed wasn't too bad. The smaller room "viewing room with TV22" was pleasantly warm. Far too warm if you were in a woolly and jacket. It also doubled as the green room. I helped the tap dancer with an awkward bit of dressing and guarded the door from outside while Danielle changed.

[Geordie McBoyne]

So what happened to the Baird studio equipment? Was it truly taken out the back door and smashed up. Or, you never know it might be at the bottom of a mine shaft.
Also, what about the Metrovic vision transmitter? Evidently this used a tetrode output valve and was designed to circumvent Marconi patents. Perhaps used a as a standby transmitter.
I understand a mechanical 405 line sync pulse generator was made and tried out.

Geordie McBoyne.

[ppppenguin]

The Metrovick TX technology, notably the demountable output valves, went on to be the basis of the Chain Home radar TX. According to Paul Marshall they were cheaper and more rugged than the Marconi valves that were custom designed for M-EMI vision TX. Excellent valves but a bit fragile and expensive by comparison.

As for where all the Baird kit went in 1937, I've never heard a word about it. Back to the iron foundry from whence it came? The film camera from the IF system reputedly turned up some years ago and is now at Bradford. There is some discussion as to whether it is the genuine article. The route it took was back to Vinten(?) and refurbished for normal 16mm use. Then spotted many years later as having an unsual plate over the hole where the 17.5mm film came out of the bottom into the processing tanks.

One point that hasn't been mentioned here is that the Baird vision system was essentially AC coupled. Unlike the M-EMI system which had black at a fixed carrier level. This wasted a lot of TX power so the range of the Baird system was potentially rather less. Baird's engineers may not have had the skills to do proper black level, may have thought it not worthwhile or there may have been patent issues.

[Geordie McBoyne]

Hi Jeffrey, Baird Television Ltd was not privy to many patents such as you have just mentioned black level referencing. Another was the frame sync consisted of just one 1.33 millisecond broad pulse.    Panrock has just posted up details of the Baird TV system on the UKVRRR. The line sync pulse was 13.33microseconds wide and the back porch was only 3.33microseconds.  Not wide enough to do any black level clamping anyway, it would have to be sync tip clamping.   Let's be honest it was a rubbish TV system with no development potential.  Did BTV really believe had a system that would last for years to come?

Geordie McBoyne.