How many hours?

[slidertogrid]

I am not sure if this qualifies as vintage but I think it is worthy of a mention...
My friend has a car servicing and repair business, overlooking the parking area is an old monochrome camera. I think this was installed around 2004. The original set that was used to display the picture (a second hand portable) failed sometime around 2006/7.
As it was the only set to hand this small black and white portable was installed. The screen was considered a little small but it was better than nothing.
Twelve or more years on it is still going strong! Well it's still working...
This is even more remarkable as the set is never switched off, it runs day and night 24/7.
I visited yesterday and noted the tube was looking a bit poor, still bright but the highlights are silvery.
I reduced the brightness setting slightly and the picture improved.
So 8700 hours in a year multiplied by 12... Can it really have lasted 100000 hours? Should we expect a letter from Her Majesty...?

Rich.

[Ted Kendall]

Originally Posted by slidertogrid

/This is even more remarkable as the set is never switched off, it runs day and night 24/7.

I expect if it were to be switched off, something would go pop on restart...remarkable, nevertheless.

[paulsherwin]

Presumably it has actually been turned off on occasion, for example during a power cut.

[kalee20]

That says a lot for the electrolytic capacitors in there!

Would be interesting to move the camera very slightly, see if the fixed features of the car park have burned themselves into the screen! Loss of contrast at high brightness could be cathode emission deteriorating.

I believe a Mazda AC/P valve clocked up 232,000 hours at the BBC before being taken out of service.

[peter_scott]

https://pdfs.semanticscholar.org/cf5...01c23cdbd1.pdf

[slidertogrid]

Originally Posted by paulsherwin

Presumably it has actually been turned off on occasion, for example during a power cut.

True there must have been the odd time that the power has failed and certainly the garage fuse panel has been changed during the time this set has been in operation.
I had to take the set apart about 5 years ago the line hold went off lock and was outside of the range of the rear user control. I looked inside and found the osc coil I set the user control midway and adjusted the coil until the picture locked. It wasn't easy as it was only possible to get the two halves of the case apart so far just enough to access the PCB I cant remember why this was but I would guess possibly the speaker lead.

Anyway that adjustment done the set came back on and has worked OK since. I don't visit very often these days so I was surprised to see the set still working there yesterday!

As far as screen burn is concerned I am not going to switch the set off to find out and the camera is far too high up to get to it!

When I had the TV shop we had an NEI mono portable in the workshop connected to a Pye camera in the shop. That set definitely had a brown outline of the shop burnt into the screen. That set also ran for years but was only on during opening hours. Like me it got a rest after 5.30pm and Sundays!

[Refugee]

I have got a little Panasonic monitir that came from a football ground that was being upgraded to wide screen for live TV coverage.
It has the cue logo burned onto the screen from all the waiting for the commercial breaks.
It is now used as a second screen on a CCTV camera looped through from a bigger colour one by the recorder.

[Heatercathodeshort]

When I visited Toshiba at Plymouth in 1985 they had a 1980 colour model in a ventilated case that had not been switched off in over 5 years.
It was absolutely filthy, covered in thick static dust. The picture was still bright through all the muck! They were very reliable. John.

[PaulM]

What's surprising about this is that it's clearly a budget model. Cathode technology improved greatly through the late 80s and 90s and by the time CRTs 'died' the life had become incredible - far, far better than could have been expected back in the 60s and 70s. The reason was the development of so-called 'dispenser cathodes' using advanced materials. This meant that high-definition computer monitors could maintain their brightness and sharpness over a much longer time - the 'sweet spot' didn't enlarge as the tube aged.

Some background here: http://citeseerx.ist.psu.edu/viewdoc...=rep1&type=pdf

There's a lot more out there with a search on 'dispenser cathodes'.

That's all very well for a relatively expensive domestic TV or a quality computer monitor, but a cheapo monochrome security monitor? Perhaps dispenser cathode technology had reached such products? I don't know.

Best regards,

Paul M

[lesmw0sec]

It is amazing how some stuff survives. I recall a Philips TV set which was in the middle of a slate mine (very damp and with water dripping on it) It had been reliably repeating a visitor info. video for years. Also underground, I supplied some old and redundant VT100's for an underground museum. They set them up so that the punters could type messages to each other. I suspect that they are still working.

[Welsh Anorak]

I wonder how many car repair garages had (and still have) the obligatory Fifties wireless sitting on a shelf, covered in overspray, entertaining the mechanics every day?

[Heatercathodeshort]

The final generation small mono tubes give pin sharp pictures and I guess will work for a life time. The 14" colour tubes fitted in the Philips CTX and KT3 models, from a much earlier period appear to be indestructible as do the TX9 and many other models. The 16" and 20" tubes had a short life. Another superb tube is fitted in the 17" philips 320 series. One of the very best. John.

[mickm3for]

Hi in Rainbows tv shop in Gravesend kent they had a tv in the window as part of a display for years the set ran at high brightness and contrast due to the light comming in the window when this set was turned off a picture of BBC test card C in negitive was on screen in those days the test card was all that was on during shop opening. No day time tv

[slidertogrid]

Yes I read somewhere that ' The test card girl ' had been on Television for more hours than anyone else in the UK. I suppose this is a record that is unlikely to be broken...

Quote from Wiki:
The most iconic image, introduced in 1967 with the advent of colour TV, was called Test Card F. Its designer was a BBC engineer called George Hersee and, for a dummy run, he had included a picture of his eight-year-old daughter, Carole, at the centre of it. The BBC decided that replacing Carole's picture with an adult model was too risky – they needed something timeless, and 1967 fashions weren't exactly built to last. So Carole went into a photographer's studio: the result was the familiar image of a girl with an Alice band, playing noughts and crosses with a rather terrifying toy clown, surrounded by mysterious test graphics. Hersee was, unsurprisingly, teased at school and, to her discomfort, the image was used on a daily basis until 1998. Now living in the New Forest with two daughters, she can claim to have had more screen time – around 70,000 hours – than anyone else in British TV history.

Rich

Rich

[McMurdo]

How things change, our local bar had a set of 'last generation' 4:3 crt tvs installed to show adverts and they were a mix of Sanyo 28in and 21-inch (or so), within a year all the 21-inch tvs had very tired tubes.

[Graham G3ZVT]

I see a surprising number of large CRT monitors suspended from the ceiling inside the entrance of large stores to deter shoplifters.

I suppose you would need to hire a scissor lift to swap it out safely.

Only this morning I was in Altrincham and noticed the big music store Dawsons had sadly closed down. The only thing left in the shop was the big CCTV monitor suspended from the ceiling.