Power supply question

My understanding is that the caps in old power supplies are the main problem with vintage electronics and that the lower voltage mainboards tend to run fine over the long haul as long as they are getting steady clean power. Servicing power supplies can be dangerous for guys like me who just replace batteries and displays. I’m curious if you can just use an off the shelf external power supply to bypass the internal and can be easily replaced as needed? Seems like the modifications would be much easier to make than trying to rebuild an old power supply and you don’t have to muck around with high voltage.
Does this make any sense?

Completely dangerous. Capacitors time expire because the electrolyte in them is corrosive and eats the internals out, then leaks though the seals. All vintage 80’s and 90’s caps have time expired.

First rule, is if you are not sure of your abilities to de-solder and replace caps, find a proper repair shot to do it. You can’t just replace caps without knowing they type and what purpose they serve. Decoupling noise, filtering, or timing. The wrong cap in the wrong place can short irreplaceable ic chips. Contact your local music shop to find a tech who can service the synth for you.

The wrong cap in the wrong polarity can cause explosions (look it up and see what happens when you apply power to an electrolytic capacitor backwards!) Dangerous indeed! https://www.youtube.com/watch?v=4yZxNKyd_lM
Start around 02:55 for the exploding cap… and it’s a small one!

My question is about replacing the power supply with a new external one, not repairing the old one. I’m wondering if this is possible and why people don’t do it?

I was looking at kits from DIYRE and thinking about building one. I noticed that the power supplies were all off the shelf and not in kit form, so you don’t have to mess with mains electricity. That got me wondering why we mess with power supplies at all? They’re not important to the sound character of the synth. Just replace them.

A lot would depend on what the power requirements are… voltages, current, that sort of thing. An old PC power supply might provide everything you need, and would be an economical and SAFE option.

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Way too many variables involved. Very few power supplies just need something simple like +/- 12V to run. Nevermind that there are some supplies that need to supply very high currents, as well as higher voltages to things like VFD’s.

It’s simpler to just fix (or have someone else fix) your power supply in the machine you have.

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