CRT TV Question
 

So I have been noticing on my 1998 RCA Console Set that when it is first powered on the picture on the screen is very blurry, and smooth looking. If you wait just a minute or so it clears up and the picture looks good. It also seems to have a bit of too much red in the grey scale until it's been on for awhile. I am wondering if this is just signs of the CRT/Picture Tube beginning to shows signs of wear and age? I would be interested in hearing what the Experts have to say.

It has the famous CTC 177AM2 Chassis.


Thanks.

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Yes those are symptoms of the picture tube getting old. Run it at high brightness and
it will continue to deteriorate. Set contrast to minimum, & brightness to a low level
and use it in a room that is dimly lit, don't make it compete with sunlit room and
you will get a long life out of it - even though it's showing signs of old age now.

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Ditto Mr Squirrels
Classic symptoms of weak CRT. Wickid easy to change if
you wanted to.

Zeno

I have almost the same question...

But is a doubt, also... since I worked at a time with only in-line CRT, I dunno if have differences to a delta-gun tube: I have one delta-gun in collection (that one I yet have to correct some purity issue), but it have excellent image only after 2 or 3 minutes; it starts blurry. And, it have a maximum contrast it can show: If I try to crank it to have a more luminous image, it blurs a lot.
To be fair, it's brightness is good for night watching...

About this contrast limit, is that manner in delta tubes, or mine is showing it's age?

I like this CRT, it render the colors very rich; outstanding!

Another doubt (a curiosity/musing) now, if people don't mind: all delta-gun CRT are absent of the black matrix, or some use it? This CRT have very low light leakage between adjacent "pixels", like modern good CRT. The focused image is second to none... (after it warms)
Or, in another words, if the black matrix concept are apllied only to in-line CRT?

Black matrix delta tubes were invented by Zenith & came out @1968.
They were called Chromacolor. They started on high end consoles.
14", 16", 19" 23", & 25" were built. Improved with smaller dots,
more HV, flatter & more square tube over the years.
@1976 Zenith came out with another new tube. The EFL " Extended Field Lens"
or Tri Focus. Deltas got phased out over the next few yrs. EFL came
in 13", 17", 19", 23" & 25" The EFL was an in line gun & phased out @1981

Zeno:smoke:

Interesting! Thanks, Zeno.

.

Yah, The Chromacolor tubes were most likely the best tubes ever made. So Zeno, a
question.... I have a 21" or so Magnavox, 2003 I think, and a 34" Panasonic HD
CRT set, 2007? and I have seen RCA's 15" that people have tossed out, Same
vintage and they all have a perfectly flat & very square picture tube, and they
make one of the sharpest pictures I have ever seen on a CRT. So I believe
the RCA set was marketed as a "Pure Flat" tube, And Samsung also had
a CRT set around the same time and maybe it was them that called the
tube "Pure Flat" but anyway these were among the last of the new
technology CRT sets I remember seeing.... You got some history
on these CRT's? I seem to recall Zenith Patenting a Pure Flat
CRT but don't remember seeing any Zenith sets with that same
look to the CRT face... Thanks.... And while yer at it spill all
the other Zenith knowledge you got squirreled away in that
brain of yours.... we're all ears... Was that ELF tube what
Zenith called "System 3" I think it may have been....

I have a 1972 23" Chromacolor floor model, it's sweet!
Awesome picture..... Love that set....



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Another CRT TV question...

Perhaps only a curiosity, but anyway:

In my short carreer fixing CRT TV's I noticed some CRT being strange in the sense of adjusting focus and G2: some become interdependent, like having leakage between the 2 electrodes. Just I have a 17" Toshiba with japanese CRT having this behaviour. But luckly, I'm able to adjust for decent focus. Besides that, this CRT is outrageously insanely bright; the pixels are more bright than the ones in my OLED in HDR mode with peak scenes, and even so it don't blooms or loses focus...

This issue, is a gas issue, is a leakage issue, or is difficult to estimate the cause?