Look closely for cold cracked solder joints, replace all eletrolytic caps (normally only good 15-20 years). Bad caps will cause other parts like bridge recifiers diodes and power transistors to burn also, so check those for shorts before power up. Some you may have to remove from the board to check accurately. You might get lucky with just some cracked solder, but when I go in I get all the stuff that might go later. Good hunting.
Plaz
(Reanimator of thousands of power supplies over the years.
)
