Replacing the transformer should be pretty simple, as it only has to supply one audio board.
Check for regulators on the board. Commonly +-15V 3term.
A 27V or 30V centertapped winding (2x13V5 or 2x15V) should provide +/- 18V to 21V after the rectifiers, to feed those. You could temporarily substitute a bench supply, to see if there was a major supply problem.
The aux lamp connector seems to expect 12Vdc.
Once it's running, you'd know if it actually needs more in-depth repair.
RL
Just in case other user needs them in a near future you can measure secondary voltages and post them here.
-- Saludos
d l
You've never seen a fire started by a cheap transformer without a fuse. I h ave. A 'service company' replaced 100 bad transformers in some old Jerrold JSX-3 and JRX-3 cable TV boxes back in the '80s instead of using the proper transformer from Jerrold. They were coming back to our office with belted cases, and in one case, the plastic case had caught fire. Withinn six month s, every one of them had failed. The original transformers were both fused and had stell end bells to prevent a fire.
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