Help with Amiga 600

[paul1981]

I bought an A600 off ebay earlier this year and when I got it home it would power on but all I got was a black screen. Then it decided to work and then seem to power down itself intermittently. I opened it up and there was a screw jammed where it shouldn't have been. There was also a screw missing from the floppy drive bracket, which of course was the one on the motherboard.
I'm guessing the previous owner had in the past replaced the floppy drive, used one of the case screws instead to secure the floppy bracket to motherboard, obviously the case screw is shorter and so it fell out of the bracket given time, and the correct screw is longer and he used that on the case so this 600 has a "nipple" from having had a long screw (tightened).
The floppy drive is really nice actually, a Panasonic JU-257A606P.

Anyway, I removed the screw, and it worked. So, check for a loose screw or something, something that may be short circuiting. You never know your luck. I was lucky it didn't damage the motherboard.

[paul1981]

Hi i removed the scandoubler, memory card and Cf disk and putted it back in again, and pressed on all chips, and turned on the power and it came back after 10 min mayby i should let it be powered on a few hours. I hope it will keep going, but who knows. I think the Amiga 600 feels a lot cheaper made, than my others Amigas.

Have a really good look at the power connector socket on the 600. Sounds like the last owner really abused your machine, and if too much force was applied to the power socket when plugging in the brick power supply it could have easily caused dry joints on the socket. Fiddle with the plug/socket whilst it's powered on and see if anything happens.

Not wanting to state the obvious here, but have you tried a different power supply yet?

[paul1981]

Hi again i use the same power supply to my Amiga 1200 and it works fine there. But i checked the power socket on the back of the amiga, and it is lose, and when i touch it when the Amiga is powered on the power comes on and of all the time. Do you know if i can fix it myself? or is it a bigger Operation.

Yes this should be easily fixable. Hopefully then it's just a matter of re-flowing the solder on the power socket on the motherboard.

First you'll need to remove the motherboard from its case (remove motherboard screws).
The board and shield comes out together (pull up and towards you).
Then remove the shield (you'll need some computer like nut driver or a tiny spanner to take the tiny nuts off of the ports at the rear).
Then look at the solder joints on the Power Socket on the underside of the motherboard. You may be able to see cracks in the solder (likely circular cracks)...but re-flow those connections anyway (5 or 6 of them).

So you'll need a soldering iron and some solder to do this and it's easy peasy.  The other possibility is a crack in some of the circuit traces, but again this should be fixable with jump wires (you'll need to find the break first though). I think this is a dry joint problem though, being as though the socket is loose, so I don't think we'll need to go there.