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video signal -leak thru to HV?

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New Member
1rst Thanks for looking...

I have an older (1987)..Toshiba..31" Diag,..works beautifully...except..

when there is no input signal,...raaster is full and clean...

when video is applied,..streaks appear,...most notable with overlays,..

and high contrast video..audio does not affect these streaks,..

suspect signal bleed through HV,....causing the resulting streaking,..as

raster is clean with no video signal...

or am i out of it here?...



When you say streaks appear, where do you mean?
Around objects?
Does the streaking reduce when the colour is backed off or brightness reduced?

Symptoms sound like flaring to me, but difficult to say without seeing...Can you post up a photo?


New Member
Hi,...thanks for the reply

no,..do not have a way to put up pic, but an example would be credits in white,..

with screen scrolling on a black background,...the streaks are horizontal,..left to right,...

and follow the scrolling credits....

maybe a leak of signal affecting cathode?

Nigel Goodwin

Super Moderator
Most Helpful Member
Turn the contrast and brightness down, see if that cures or helps it.

Sounds like the video outputs are been overdriven, commonly caused by a low-emission CRT.


New Member
as our sojourn continues....

no,..still visible even with an almost dark screen,...tried both,...no effect

lo emmision sounds like a major ugh,...tho set is from '87,..

can signal affect cathode emmision?..or is it time to loose this set?

hate to do that,....

thanks again

Preher TV

i would say with the age of the set, the CRT is weak, with these older CRTs because the "getters" they used were much better than latter CRTs you can possibly rejuvinate the CRT if you have the equipment...otherwise 86 that piece of CRT crap..lol.........
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