Dead Apple iie restoration, looking for help along the way
Early Apple iie not working uk pal version two disk drives and monitor, thought this would be a good restoration project to kill some spare time and learn some new skills on the way.
Stripped down removed motherboard checked for obvious faults, ensured all chips where well socketed general clean down of motherboard.
Removed power supply opened for general inspection of capacitors all look good to me, no obvious swelling of bulging on tops. Ordered replacement wima capacitor. Plugged power supply to check voltage + 11.30 - 12.56 and + 4.84 / -5.25 thought these were a bit on the low side but still working , plugged power supply back into motherboard and power led glowed for a second with residual power thought that was a good sign, Time to try first power up and see how far i get,
Not far at all, no beep from the speaker, nothing on the screen and no power led on the motherboard, good start, checked cables and tried a few more times, same result, noticed that I get dim flicker from the power supply when I turn off. Short on board or psu stalling under load was my guess. Should have said at start this is all new to me first stab at vintage computer restoration. Checked the motherboard again with nothing obvious, stripped power supply again this time taking the board out of case to have a closer look at the bottom of capacitors again, nothing obvious. Have posted a couple of images of psu. If anyone can see anything of interest, it would be much appreciated or an article on how to troubleshoot psu as I don't really have a clue where to start apart from replacing all the capacitors and hoping for the best. Checking a few points on the motherboard no sign of voltage will need to look up exact points to start tracing power , again any advice would be much appreciated. Hope to keep this thread going for my own reference and help the next person making the same mistakes as me, so far all good fun and plenty of head scratching.