exxos's Atari, Amiga & retro forum

Acquired a filthy 520 ST recently and just going through the process of servicing it. Here is the PSU.

Also, link to Icky's post about his PSU.

Chip is NE5561N
Caps are 2x 470uF 25V and 3x 4700uF 16V


Start to finish:


Put some capton tape over the wires as I didn't like the idea of them being naked like that...


Decided to ESR test a couple of the old caps to see how they were doing:

4700uf 16v:
5612uf
Vloss = 1.6%
ESR = 0.17 Ohms


470uf 16v:
544.7uf
Vloss = 0.8%
ESR = 0.22 Ohms

That is a nasty looking PSU, not keen on that potting or the bare wires. It's power without the price for sure........

I had to build one for my own 520ST, thanks for internals Meanwell :)