Re: Sony 2SD625 line output transistor
The set is now completely dry. I left it long enough before applying power (12V current limited) to it.
The mains transformer insulation seems OK and it runs on mains. There seems to be a hum bar which seems to be drifting with respect to the picture so probably mains hum. Most likely just the smoothing cap. That didn't show up when it was being run on the 12V psu, of course.
As to the dampness, I was thinking that sets like that were often used in caravans and even boats. Maybe it got left in a damp caravan . The timebase board print side is up, assuming the set was left in its normal viewing position. There is a grill right above the entire board and the print side was covered in "gunge". The component side of the main board (below the timebase board) was also in poor shape and the screening cans were very rusty. The print side of the main board looked like it had just left the factory.
Going to check the bridge rectifier and smoothing capacitor on the mains input side now.
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