Mitsubishi 1992 model help

[Ken G.]

This is the big 36`` set date of 92 . It has many fine lines runing from
side to side of the screen on top of a good picture . On top of bright
images there are patches of sparkly snow . When the snow spots show up
the sound statics on top of good sound .
What circuit should i be looking at ?

I already replaced about 15 capacitors that had black goo running down
its leads .

Thanks

 

[Leonard Caillouet]

You are about half way there. Keep looking for bad caps.

Leonard Caillouet

 

[David]

You need to ESR ALL the electrolytic capacitors, remove the big ones and
have an out of circuit test. You are about 1/3rd the way to fixing the set.
David

 

[Ken G.]

Thanks guys .... i did ESR the leaky caps with a Cap Wizard tester &
they tested good !
This has about 500 capacitors in it ... guess i`ll have a good stiff
drink before i go back in

 

[Leonard Caillouet]

Thanks guys .... i did ESR the leaky caps with a Cap Wizard tester &
they tested good !
This has about 500 capacitors in it ... guess i`ll have a good stiff
drink before i go back in

If a cap is leaking electrolyte, don't even bother to test it, change it.
The electrolyte itself and the related corrosion is often the source of many
problems.

What you need to do is find every cap that is leaking electrolyte or bad in
any way. You can fix most of these sets by just getting the ones that are
leaking, cleaning the board of all electrolyte and corrosion, and repairing
any damaged traces and bad solder joints.

There are several ways to identify the leaky caps. First, look at the
component side of the board for wet spots and black corrosion on the solder
side. Second, visually inspect for black goo on the leads and bulging of
the gasket. Third, heat the legs and smell. the smell of electrolyte is
unmistakable and is like bad fish.

The leakage will typically be on the negative lead. The caps may test good
on all parameters.

Make sure that you wash the electrolyte off the board and scrape the black
spots off of the traces to avoid further corrosion.

Leonard Caillouet