I too have the problem where C80 has disintegrated so intend to replace this and C80. Board is very discoloured around Z3 and Z4 also so will prob look at replacement also. Can anyone confirm the spec of the zener diodes

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I would think that if the zener diodes CR3 and CR4 were replaced, the replacements should be elevated above the PC board surface - one, to get better air circulation around the part, and two, keep these obviously hot-running components from further charring the board.

 

I would think that if the zener diodes CR3 and CR4 were replaced, the replacements should be elevated above the PC board surface - one, to get better air circulation around the part, and two, keep these obviously hot-running components from further charring the board.

Hello, thanks for your reply. Makes sense to me!
Can you or anyone tell me what voltage rating I should order for the diode replacement parts please?
Thank you.

 

The same value parts should suffice.

The main thing is to get the parts in question at least 1/8" - 1/4" above the board.