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  #1  
Old 02-26-2024, 05:52 PM
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Username1 Username1 is offline
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This picture does contain picture information, however, it looks like a AGC
problem + Brightness way too high, and is displaying retrace lines.

But, since you replaced all the capacitors, as you stated, it can be anything
from the wrong part in the wrong spot, mistake in wiring, or something
else..... Along with this on the picture, is there quality loud sound? or
is it low, or does it have some noise mixed with it?

Use clues in pix, & Sound to guide you, + Check your work, + Check AGC.

Looks like sync is locked, Video is pretty weak - find the cause.

I would say the ion trap is fine for now, and the picture tube is fine too.

-----

Addition:

When I say it looks like a AGC problem, I mean - If the set were not
completely re-caped and you know for sure the circuits were not
mistakenly changed to cause this loss of full signal at the point
it's lost now.....

Start by checking your work - especially signal path near and
after the detector circuit + Possibly include the AGC stuff.....
Don't discount possible bad tube, open IF Transformer, etc.

But first check your own work for mistakes....



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Last edited by Username1; 02-26-2024 at 06:08 PM.
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  #2  
Old 02-26-2024, 06:15 PM
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Kevin Kuehn Kevin Kuehn is offline
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Try turning your room lighting off. Next turn down the TV's brightness control, and see if the picture(contrast) control can give you a more defined with better contrast picture. With the brightness turned down you may get better focus control too. Keep in mind you can't increase screen blackness with the TV's controls unless the ambient room lighting is low. Think of it as a movie projected on a screen, and if you bring the room lights up too bright you loose picture contrast. These early CRT's were never intended to be viewed in a well lit room.
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Old 02-26-2024, 07:07 PM
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Yamamaya42 Yamamaya42 is offline
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Quote:
Originally Posted by Kevin Kuehn View Post
Try turning your room lighting off. Next turn down the TV's brightness control, and see if the picture(contrast) control can give you a more defined with better contrast picture. With the brightness turned down you may get better focus control too. Keep in mind you can't increase screen blackness with the TV's controls unless the ambient room lighting is low. Think of it as a movie projected on a screen, and if you bring the room lights up too bright you loose picture contrast. These early CRT's were never intended to be viewed in a well lit room.
true, but the image should not be THAT dim, something is not right here.

example, my set.
http://suzaku.live-evil.org/0226241857b.jpg
Taken with VERY bright light on, but then again my 12LP4 is an exception, having spent more than half of it's life in a basement unused!
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Old 02-26-2024, 07:42 PM
old_coot88 old_coot88 is offline
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By golly there is a locked-in picture there. Couldn't see it at first. First thing I would look for is an open peaking coin the video chain, anywhere between the vid detector and CRT. Blooming is generally from HV being lugged down due to a weak HV rectifier.
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