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G0TEZ > TECH 03.11.09 08:23l 117 Lines 4925 Bytes #999 (0) @ WW
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Subj: JLB,TV. unrecorded facts.
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From: G0TEZ@GB7FCR.#16.GBR.EU
To : TECH@WW
The following is a repeat of something I sent out around 1995.
I thought it worth repeating in light of some stuff I have seen on the
'net and a TV film about the true inventions of John Logie Baird.
In 1963 I spent a month in hospital in Manchester where I was living. In
the next bed was a man around 50 who was, like me, a TV engineer. He had
his own shop not far from me. Naturally, we talked a lot, especially after
he told me that he had been one of Baird's assistants during WW II.
I had believed up 'til then the usual stories about the unemployed
Scottish shoe salesman who cobbled together a poor quality TV system with
spinning discs and mirrors which was superseded by the far better Thorn
EMI electronic 405 line electronic TV system which came into use in the UK
in 1946.
What he told me was very surprising to say the least but it was obvious
that he knew what he was talking about.
He told me how, contrary to published 'fact' at the time that JLB
continued working on TV during the war and he was one of his assistants.
He told me how Baird had worked on electronic systems up to 2,000 lines,
Not only monochrome but in colour.
He said that JLB had recommended to the BBC that they adopt 625 line -ve
modulation, interlaced pictures with the newly invented FM sound.
The BBC went ahead and gave us 8" and 9" 405 line +ve modulation TV with
AM sound.
It wasn't to be until the late 1950s that they changed their minds and
gave us the awful, expensive 'dual standard'TV sets with their clunking
system switches, operated by solenoids as we changed channels which caused
the majority of faults, especially when we settled on PAL colour on one
channel only in 1967.
He also came up with a convertor which could change a conventional
monochrome set into a CTV. The principle was simple, at the TX the cameras
cpuld be set to run at double the normal frame speed with a colour
splitter
compsed of two filters, one above the other, the top one orange, the
bottom one cyan,
At the RX the frame time base, as we called them then could be set to run
at double speed, producing two pics, seperated vertically and an adapter
hung over the screen to recombine the two pictures by means of dichroic
mirrors and lenses to recover a colour picture.
I asked him what the quality of the colour was like; we had both seen
demonstrations of CCTV using 405 line NTSC colour which was pretty good.
He replied "adequate",
We went on to discuss many more things like stereoscopic TV and the
language baird used, such as referring to seven different blacks, which I
assume to be a way of referring to grey scale.
I left hospital about three days before him and, as he had given me his
phone number, I rang him, partly because he had told me he had the chasis
of three projection TV sets in his cellar which I could take away and
experiment with. The 'phone was answered by his tearful wife who told me
that he had just died.
Naturally, that put an end to any ideas I had had about meeting up with
him
and attempting to make a CTV.
==================================
That is the gist of my packet msg around 1995. Packet was very busy back
then with some very interesting people. Not the bunch of people arguing
about boring subjects and insulting each other.
I got a few replies, one of which told me to read a book called Vision
Warrior published by Scottish falcon. I ended up buying it and still have
it. There ws nothing in it about the colour convertor or Bairds
recommendation re: 625 lines interlaced -ve mod with FM sound.
Yesterday, I decided to look at a website and typed in 'John Logie baird'.
I was only expecting the same old "inferior TV" rubbish but was peasntlt
surprised to find sites praising Baird. Typical was:
www.bairdtelevision.com/war.html
It has nothing about the things mentioned above but is refreshingly
honest.
Then, tonight, there was a film, presented by Baird's son Prof: Malcolm
Baird who had taken no interest in TV and became a lecturer at a Canadian
university.
Both the website and the film give far more information about what really
happened during WW II. In fact one of his biographers said he couldn't
understand why we hadn't been watching large screen, colour TV since WW
II.
He mentioned how baird's 3d system which doesn't require glasses is about
to be incorporated in the next generation of TV sets.
It is all a big mystery.
I have long forgotten the name of the man in the hospital. There is
frequent mention of Baird's two assistants whom he paid out of his own
money but they don't seem to be named and there is nothing about a man who
went on to start a shop in Manchester.
Any info would be welcome but, please try to resist the temptation to send
bulls with snide remarks and / or accusations of a defective memory.
73 - Ian, G0TEZ
Msg timed: 02:52 on 2009-Nov-03
Message sent using WinPack-Telnet V6.80
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