Philips PM 3065 Oscilloscope repair help

[afsar]

Hello guys,
After a long struggle , I got Philips PM 3065 old CRO to test my circuit but unfortunately, it is not working. I tried to fix it but as a beginner, I could not find it where to start fixing. I had open the case and found power supply was making the whistling sound. As a new one is too costly for me so please help me.

[cheeseit]

Check the electrolytic capacitors on the PSU board, some or most are likely bad with high ESR and/or are low capacity.

[Shock]

Measure the capacitance and ESR on the secondary filter caps and replace if needed.
Replace the Rifa X2 if it's an original, bound to catch on fire eventually.