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Vintage Television and Video Vintage television and video equipment, programmes, VCRs etc.

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Old 19th Mar 2013, 11:20 pm   #21
McMurdo
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Default Re: 80s Colour Projection Sets

We used to repair the ones for pubs, a few Seleco but mainly Vidikron. We had corrosion problems, triplers/EHT splitters failing, PSU problems and the odd low tube, usually Panasonic or Thomson. Barco were a league above, indeed they still make video projectors..though LCD based now. Watchers of the impressive Diamond Jubilee images projected onto the palace via Barco projectors will appreciate how things have moved on since 'The Big Match Live on the Big Screen' pub posters!
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Old 19th Mar 2013, 11:29 pm   #22
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Default Re: 80s Colour Projection Sets

I nearly bought one of these a while back. It was really cheap (about 50 quid) needed a bit of remedial work but for the size i would have been super happy.

I didn't in the end for a number of reasons. A) I would have had a job getting it home, it was a long way away. And B) I wouldnt have been able to get it up the stairs or through my bedroom door.

I'd still love one though!
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Old 20th Mar 2013, 10:48 am   #23
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Default Re: 80s Colour Projection Sets

When I worked for a short time in the 1980's at Imperial College, London we had (among others) a Barco video projector which was mounted on a large trolley and could be wheeled around. Some lecture theatres had 3 gun permanently fitted projectors.
I used the trolley mounted Barco at Imperial College in their main hall once and ran a Flash Gordon video through it for my own amusement. The hall had a large screen and good sound system. (It even has/had an organ).
They were in my opinion they were never quite bright enough. How different to he LCD or DLP projectors today.
I had an old Sony CRT projector one at home once, (came from a public house) so big and heavy I gave it away.
John
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Old 20th Mar 2013, 12:28 pm   #24
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Default Re: 80s Colour Projection Sets

I recall much confusion in a lecture-theatre when a Canadian-made "Electrohome" CRT-based projector was wheeled in, connected up to an early PC (this would have been in the mid-1980s) with the intent of demonstrating a spreadsheet (Visicalc?)

The image said device produced on the screen was clear and sharp but mirror-imaged on its vertical axis. Turned out the Electrohome projector had a concealed switch which was set to "back projection" mode. That took some time to find...
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Old 20th Mar 2013, 2:28 pm   #25
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Default Re: 80s Colour Projection Sets

There was a projection TV in the Students' Guild at Aston University when I was there. The convergence on it was totally mis-set; resulting not so much in colour fringes around edges, but almost three independent pictures! I once spent a spare half-hour getting the picture spot on, and it stayed right for a few days.
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Old 20th Mar 2013, 9:03 pm   #26
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Default Re: 80s Colour Projection Sets

This has certainly evoked a few memories, so thanks for the contributions.

What were the EHT arrangements for running 3 projection crts? Did they each have their own LOPT or did one split unit serve the lot? Were the EHT voltages particularly high to run these tubes?


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Old 20th Mar 2013, 9:26 pm   #27
bobbyball
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Default Re: 80s Colour Projection Sets

As I recall, there was a single LOPT and tripler but a splitter to feed the 3 tubes...

Robert
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Old 20th Mar 2013, 9:43 pm   #28
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Smile Re: 80s Colour Projection Sets

Hi,
I used to have a Decca 1000 monochrome projector TV from 1951. The EHT was 25Kv on the 3.5" Mullard tube. It had an oil filled tripler with three EY51s within. That was frightening enough! So, I'm curious too as to what EHT arrangements these triple tube projectors had. It must be quite a current too to drive three tubes flat out.
Cheers, Pete
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Old 21st Mar 2013, 2:55 am   #29
emeritus
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Default Re: 80s Colour Projection Sets

Here's scans of a leaflet for the Decca 1000, and the Advent Videobeam that I mentioned in my earlier post.
Attached Files
File Type: pdf Advent VideoBeam.pdf (408.9 KB, 79 views)
File Type: pdf Decca 1000.pdf (1.73 MB, 90 views)
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Old 21st Mar 2013, 2:54 pm   #30
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Default Re: 80s Colour Projection Sets

Hi
Like many above, I used to look after a few of the Eighties wooden beasts - Mitsubishi and Panasonic, I think. They were quite reliable, but gave a really poor picture - when used in a pub most people watched the normal TV instead.
Then came the better sets in the late Nineties, Toshiba being pretty good, though the ubiquitous Samsung wasn't too bad until the convergence ICs died. Usually faced with the cost of replacement (you had to use genuine Samsung supplied parts as they were the only ones that worked) a ladder or broom handle would mysteriously find its way through the screen and the insurance company would be called, though they very soon got wise to this ploy.
Others I saw were Thomson (not too bad, LOPTs and LT capacitors causing the most trouble) though one based on the ICC8 was a pig as it could burn a spot on each tube for no obvious reason, not unlike its Fifties predecessors.
Then we had the LCD projection sets with one fiercely bright (and expensive) lamp and an optical engine all in the cabinet, Samsung and Sony being the front runners on these. Again, you needed to sit at the right angle, but if you did the pictures could be really good, though 2000 hour lamp life could equate to less than a year's heavy domestic viewing, and extended warranties rarely covered this. Enter the aforementioned broom handle...
Of course concurrent to this was the 'stand alone' projector. Originally incredibly heavy and difficult to set up properly, the advent of LCDs brought the small and light projector which Sanyo made their own, though there were many others, some DLP and some three colour LCD, and now some truly horrible cheap imports with either a halogen lamp with transformer ballast or a spotty LED light source.
I could add my experience of a "projector" that was used in a very small gentlemen's cinema in Soho. It was a Seleco 14" domestic portable TV. modified to give over 32kV EHT with the picture inverted both ways and focused through a big lens. Amazingly after many years' heavy use the CRT was fine, but the tripler had broken down. You'd be astonished how bright an over-run CRT can be! And, no, I never saw it in situ, though I suspect the gloom only added to the experience. Shudder.
Glyn
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Old 28th Mar 2013, 12:30 am   #31
Mike Fulton
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Default Re: 80s Colour Projection Sets

Along with the japanese units which were very reliable, we repaired Philips projectors which were sold from the two trade shops for whom we did trade service (Durham & Washington).

The sets were pretty trouble free, the only faults being the usual tuning capacitor problems which are so easily fixed in Philips sets of that era, however I am amazed no-one has mentioned the flaking paint problem associated with the Philips projectors (did I have to do them all)??

The problem was that the cooling fluid used to attack the black paint inside the cooling couplers, resulting in the paint flaking off and lying upon the face of the affected CRT, resulting in a spot of missing colour (R,G or B) on the screen.

Philips' fix was to remove the coupler and replace it with an improved version, along with the fluid, which was by this time also milky white.
This fixed the problem until the set was returned, by which time further flakes which had been disturbed by the work on the first tube fell from the other couplers resulting in mutliple blotches of missing primary colours. Lesson learned - replace all couplers & fluid in one go.....

Not really - when the set was returned with new couplers, fluid & cleaned CRTs, the picture was so much brighter that degradation of the blue gun focus was now noticable and futher compaints followed about the teletext being blurred on the blue writing. Replacement of the blue CRT resulted in complaints of the red & green not being as good as the blue.....

You guessed it, estimate for 3x CRTs, 3x couplers & 3x fluid kits

- Game over -
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