Updating an Amiga power supply

This is the finished project. As well as being the size and shape of a house brick, it used to be the same weight as one too. It ran hot, and it's risky to depend on a supply that's decades old.

I'm sure that the credit goes to Neil at Retro Man Cave. I'm pretty sure I saw this upgrade in one of his videos and then discussed it with him, although I can't find the exact video now. Ms Mad Lemon has also done the same thing, so credit to her too.

I have three Amiga PSUs and they're all different shapes and sizes. This is my largest one, and it's the one that is the right size for the Mean Well power supply which is recommended for this project. Further below is a shot showing the part number. It happens to have +5v, -12v and +12v out ,which is exactly what the Amiga needs. It also fits this case snugly. Almost as if it were designed for this job!

I bought the new supply a year ago, but couldn't get into that plastic case. The screws are a long way down a narrow hole and seemed welded into place. It takes just the right screwdriver - long and thin enough to get into those narrow deep holes, fit the heads perfectly, and have a good handle for plenty of torque. I've only just managed to buy the perfect screwdriver for the job!

The original supply has a switch and fuse on the mains side which I wanted to keep but didn't want to have to bother connecting up again. So I kept one end of the circuit board. Chopped it off neatly and removed some stonky capacitors from that part.

This is the fun bit, scrubbing the plastic parts nice and clean.

The new supply fits the case as if it were made to fit in there. I just needed to Dremel away a tiny bit of plastic that was in the way.

Although the supply is a snug fit in there, it probably would have shaken about. There are a couple of spare holes in it to anchor it in place. Another job for the Dremel with a little drill bit and a small machine screw and nut. I guess hot glue would do the trick too. You can see in this shot the little trimmer for the 5v supply. I didn't need to touch that as it seemed to be spot on.

I have a little screw head showing underneath. The bottom of the case has feet so that's no problem.

This all works so well, you can even use the existing wires and cord restraints without trimming them or needing any extra. This is the finished 'inside' shot. The power switch looks wonky but once the two halves of the case go together, they grip it in place.

Finally, here it is in situ, looking beautiful and working perfectly. I'm looking forward to it getting dark tonight as the new supply even has a green LED!

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