English Amiga Board - View Single Post - Amiga 500 PSU ref P.312503-03 singapore (Heavy PSU)

amigasith · 02 December 2014, 21:35

I desoldered one of the smaller capacitors in order to get room for replacing one of the potentiometers, and there was no leaking underneath it at all. Also there seems to be no leaking underneath the large ones either. For the time being, I will leave them alone. Let's see how things look like in another 25 years

Anyway, I just wanted to report back that I replaced the -12V voltage regulator and now my PSU works again like a charm

I had the Amiga 500 running for almost 12 hours and it worked without any issues at all.

There are quite a few voltage regulators in this PSU and I really don't know why the -12V one died first. The only thing that caught my attention was that the aluminium cooler for the -12V voltage regulator is much smaller compared to the others. The reason for this is probably that there is only very little room left where the voltage regulator is placed on the PCB. I added an additional thin aluminium plate so that it gets cooled better than before, and I hope that this will make it last longer.

Here is how it looks like now:

02 December 2014, 21:35	#12
amigasith Registered User Join Date: Jan 2013 Location: Wild South / Germany Age: 48 Posts: 271	I desoldered one of the smaller capacitors in order to get room for replacing one of the potentiometers, and there was no leaking underneath it at all. Also there seems to be no leaking underneath the large ones either. For the time being, I will leave them alone. Let's see how things look like in another 25 years Anyway, I just wanted to report back that I replaced the -12V voltage regulator and now my PSU works again like a charm I had the Amiga 500 running for almost 12 hours and it worked without any issues at all. There are quite a few voltage regulators in this PSU and I really don't know why the -12V one died first. The only thing that caught my attention was that the aluminium cooler for the -12V voltage regulator is much smaller compared to the others. The reason for this is probably that there is only very little room left where the voltage regulator is placed on the PCB. I added an additional thin aluminium plate so that it gets cooled better than before, and I hope that this will make it last longer. Here is how it looks like now: