At 15:57 -0400 11/1/11, Charles E. Fox wrote:
>At 02:04 PM 01/11/2011, you wrote:
>
>>On Tue, Nov 1, 2011 at 2:34 AM, Charles E. Fox <[email protected]> wrote:
>>> --      Many years ago when I did TV repairs we used to apply stuff called
>>> corona dope. Try Radio Shack.
>>
>>Interesting suggestion.  I did a little more searching and read that
>>sometimes flyback transformers can crack from overheating or aging.
>>If the internal high voltage is creating a corona/plasma since it is
>>exposed to air, does it mean that my transformer is still OK?  I am
>>guessing if there was internal shorting, that the part would already
>>have gone bad.  Does the corona dope need to seep into the transformer
>>to fill voids or do I just need to seal the cracked surface of the
>>transformer?
>>
>>Thanks,
>>tt
>>
>>--    I haven't had occasion to use this stuff in fifty years, but don't 
>>think you will harm anything by applying it in the area where the corona is 
>>visable and letting it dry before powering up.
>>

Neat pictures. It really helps to open the dark one in something that allows 
you to play with colors and contrast.  But I don't have any answers and it's 
not a cracked solder joint.

Those coils, inside, are probably would with metal foil that looks a lot like 
the aluminum sticky tape that comes in a roll.  It's conceivable that one turn 
is sparling to its neighbor and somehow the light is getting piped to the top 
where it gets out. But through the opaque plastic covering?

The red paste looks like GE Glyptal, a paint like product that is found in 
laboratories and used for the likes of repairing small vacuum leaks and high 
voltage insulation. I wouldn't expect to find it on a new flyback coil 
especially in a hand painted blob. Someone else may have been bothered by the 
sparks.

I'm staring at an SE analog board from which I have stolen parts.  Flyback in a 
case like the picture 157-0042A  TAI-HO Taiwan 08730 visible on the coil near 
C13.   Colorado Springs. CO USA 80919. Want to try it out? I seriously doubt 
that I'll ever get around to using it.


-- 

--> From the U S of A, the only socialist country that refuses to admit it. <--

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