Amiga 1000 PSU, Bad Voltages?

[AmmoJammo]

I purchased a very used Amiga 1000 a few months back, and before simply plugging it in, I decided to test the PSU.

The 5volt rail, is a bit low, at 4.9volts, while the 12volt measures at around 9.5volts, and the -5volt is at -4....

Looking in side, the +12volt, and -5volt both appear to use linear regulators? In fact, the -5volt rail uses a positive voltage regulator doing something weird...

There's some weird ripple on the 12volt line, suggesting around 8volt minimum, 12.5volts maximum from memory, but with an average of 9.5volts.

It didn't seem like a capacitor issue, but I replaced all the output capacitors anyway, and sure enough, the voltages are still off.

Should I just give up? Or do the rails need a load to properly regulate?

Thanks!

[AmmoJammo]

The +12volt and -5volt are both linear regulators off the switchmode supply, so as long as there's above the drop out voltage being fed in, they should regulate.

Unless the 5volt rail needs a load, so the switchmode controller is running harder to keep that supply up (its all one transformer, but with multiple isolated outputs)

[AmmoJammo]

I stuck two 15ohm resistors in parallel across the 5volt rail (600ma load), and sure enough, the other two rails came up to a more reasonable level.

Thanks for the help!