Casio TV-8500 Green Screen

[JohnCT]

Originally Posted by PortableTV

I opened it up. No discernable smell.

There's only 4 caps on the back of the screen, 2 are larger SMD's so at least I can change them. Fingers crossed that that's the fix. The main board has a bunch of regular caps but almost a dozen tiny SMD's that I would have zero idea how to go about changing.

I guess we'll see...

If there's no smell, it might respond to heat. *Gently* warm the boards with a hair dryer and try again. If it produces a picture, the easiest way to find the offending cap(s) is with a scope. Most of those caps are bypass, so there will be no signal on the neg side (assuming common ground) and very little signal on the pos side. Most caps should have about the same amount of "hash" on them. If you find a cap with a double or more the amount of noise on the pos side that the others do, the cap is prob bad.

Before you change it, make sure it's not a coupling cap where the same signal would be on both sides of the cap, so move the scope to the neg side. If there's no signal there, it's a bypass and prob bad.

John