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View Full Version : Broken Amiga 500+ Anyone know much about repairing these?



woody.cool
20th August 2008, 19:29
I dug my A500+ out this afternoon, turned it on, and it keeps rebooting before the Kickstart screen appears. :cry:

I looked at the motherboard, and it appears that the battery has leaked (there's some blueish crusty stuff on the board around the battery).

Any ideas on how to repair it?

When I turn it on, I get a dark grey screen, then a light grey, then a white screen - then it repeats over and over again.

Harrison
20th August 2008, 21:39
So it doesn't actually get to the insert disk purple screen?

It is never good when an internal battery leaks. This is going to happen more and more to retro fans as the batteries in our hardware gets ever older. I was thinking the other day about the battery backup in the SNES catridges and wondering if my SNES collection is still OK. I need to check those carts.

Back to the Amiga. First thing to do if the battery has leaked is to remove the battery and then clean up any left over leakage with some cleaner. The best thing to use to clean it with is an isopropyl alcohol solvent. Although I normally use carburetter cleaner as it is just as good. I squirt some into the cap of the container and then use cotton buds to clean the PCB.

woody.cool
20th August 2008, 22:52
So it doesn't actually get to the insert disk purple screen?
Exactly, it doesn't get to the purple "insert disc" screen.


Back to the Amiga. First thing to do if the battery has leaked is to remove the battery and then clean up any left over leakage with some cleaner. The best thing to use to clean it with is an isopropyl alcohol solvent. Although I normally use carburetter cleaner as it is just as good. I squirt some into the cap of the container and then use cotton buds to clean the PCB.
Problem is, that the battery isn't easily removable - the clock batteries on an A500+ are soldered to the mobo! This will require de-soldering, something I can do, but not an easy task.
On top of this, the battery acid has leaked over one of the smalled chips on the A500+ motherboard, which is probably why it doesn't work any more.

If it helps, the motherboard is a revision 6A.

I can take some pictures of this, so you can see if you would like.

Harrison
21st August 2008, 08:34
You might be able to cut the battery from the motherboard with some wire snips. That is what I do with my A4000 and it was fine. Just be careful not to slip and damage the motherboard.

Some pictures would be good. I think Zetr0 will be the best guy to then tell you exactly what will need to be done to repair it.

woody.cool
21st August 2008, 13:55
I'll try and get some photo's uploaded later (when I get home from work)

woody.cool
21st August 2008, 18:47
As promised, picture:

http://woody-cool.no-ip.biz/pics/a500p_damage_sm.jpg (http://woody-cool.no-ip.biz/pics/a500p_damage.jpg)
Click the image for a larger version

I did take more, but they're out of focus quite badly. Notice the crusty blue stuff on the lefs of the chips!!!

Zetr0
22nd August 2008, 03:00
@Woody.cool

thanks for the picture...

that leak is nasty... okay.... this is not good.... not good at all.... the Motherboard is infact 4 layers (two each side) so its tricky at best to sort this out.

Firstly that bat has to go... the 74LS244N and the 74LS373N has to be replaced, as does the capacitor, the IC socket has acid errosion on the pins, this will need to be removed or replaced.

All in all not a quick job by no means...

you will need to remove those components, nutralize the the acid and clean the board. then solder new components on.

I have both the Logic chips, cap, possibly IC as well, theres no gaurntee that this would work as its possible the acid has eaten between layers and caused a short, however saying that its a good sign that you get to boot and then a reset.

khaxzan
22nd August 2008, 04:59
Want a hammer? :owned:

Zetr0
22nd August 2008, 10:57
@woody.cool

your Amiga's plight has melted my heart, I can attempt to fix it for you, no garuntee though...

Infact i would be surprised if anyway could garuntee that fix LOL...well maybe JJB he's very good. but the postage to france only would easly pay for a working one from ebay!

its upto you woody, i wont charge other than postage, and all you need to send is the mobo :) imma based in the UK.

Harrison
22nd August 2008, 11:15
It is true that you might be able to get a replacement motherboard, or even another A500+ for the price of posting the motherboard. At least that way you would guarantee a fully working clean motherboard.

Although Zetr0 does like a challenge! ;)

woody.cool
22nd August 2008, 14:11
I spotted a repacemt A500+ mobo on ebay VERY cheaply. That might be the better option!
I could even get a replacement A500+ quite cheaply. The gutting thing is that the casing and keyboard are immaculate, no sign of yellowing at all. This machine has been VERY well looked after, especially since I've owned it since the age of 11!