Old A500+ issue..

[scuzzb494]

This is my recent battery removal. I tend not to over do on the messing with stuff to be honest. You have to kinda work with one thing at a time. So I tend to go for power, main processor and gently reseat chips one at a time. Also leave running as you have and then do a soft reboot over and over. Try another power supply and also disconnect the floppy and maybe hitch up an external floppy and check the power to the floppy. In the first instance it really is a case of seeing actually if the blood is running round the system.

Not much help. Impossible to diagnose exactly what has fractured. But as kit gets older you run the risk of damaging even more by taking the kit apart. Like I say start small with one thing and then work your way around. Could be anything... even the keyboard. I just watch the patient from my small moves and leave big spaces between what I do and also listen for odd things.

http://www.scuzzscink.com/amiga/scuzzblog_october17_5/car_sbd_231017_109.jpg

http://www.scuzzscink.com/amiga/scuzzblog_october17/scuzzblogdoctober17_2303.htm

Sadly you have to catch the 500plus early as it can be quite destructive. Also overcleaning can be a bit toxic sadly. Clean up and neautralise the battery cleaning process. Always allow the board to dry.

This killed a 500 that I once had. I get the things out as soon as I can to be honest.

http://www.scuzzscink.com/amiga/scuzzblog/car_may16_04.jpg

This'll make you giggle. I swapped the 500Plus for a 500 mobo cus in truth it never really matters to me.

Good luck. Fun times.

[scuzzb494]

Hi

You saved my life tonight.. well the life of an A500Plus. I grabbed one of my computers and set the camera up to take some pics of the motherboard for you to check those holes. Anyway when I opened the machine up I not only found a battery on the main motherboard but also on an A501 RAM board in the machine.

http://www.scuzzscink.com/amiga/scuzzblog_november17/scuzzblogdnovember17_0502.htm

So a big thanks for that. I think I saved the computer. I will find out tomorrow. The above links to all the images of the battery removal. Includes also those areas where you have holes but my board does not. Maybe it helps. Not sure.

Many thanks

[scuzzb494]

Thankyou Scuzzb, that is a help, im sure it's prob a through hole that was missed when it went through the wave, as many are filled. I may fill it when I put in the patch wire. Another question, are the chips replaceable? I can find them online, 74LS244N, so can I just swap one out for a new one?
 
 Glad you managed to get the battery off, hope the board is ok

I am not sure whether you can desolder the fixed chips and replace in truth. I am sure someone else here could advise on that. I wouldn't have thought it was a problem though for me I would be swapping out the motherboard because you are hoping to fix a problem that may in truth just expose another. I have spent way too much time trying to get busted kit working just to find its a hopeless case. Saying that I tend not to give up and do come back to problems over and over.

Keep a search open on Ebay and watch for old 500s [ busted and broken ] to appear and snaffle what you can for as cheap as you can. Having spares is always very useful.

Your photography and cleaning processes are excellent. I trust you are going to try an make a log of your efforts and create a little web page for it. That way others can learn from your experience.

Matters not in the end whether you are successful or not in truth as long as you enjoy yourself. Getting the Amiga working again would be a real bonus. So I hope you are successful. Don't give up.. but maybe do some sideways thinking [ get some spares ]

[scuzzb494]

Just a quick update, 2 trace links soldered, switched on & held my breath..



Incredible! What a surprise to see that lovely boot screen after so many years. This a500 was bought by my father back in 92, and he loved this machine. Just wish he were around to see this working again, I'm sure he would be very happy.. just as I am. I will press on now, and continue to restore this old girl back to her former glory, just hope she works when it's all back together!!

Thanks for all the help and advice here, much appreciated
I will continue to post some progress when I have the time.

Michael T

I admire all your efforts. I just wish I had that level of expertise with electronics. It really is just magical to see the Amiga back up and running. Well done.

I took the easy way out today and just swapped out the motherboard. She was the only one that I just couldn't get working.

http://www.scuzzscink.com/amiga/scuzzblog_november17/scuzzblogdnovember17_1001.htm

If you check out the blog I've done several pages on the 500Plus computers that I checked. Like I say the one above was the worst. No chance.

Anyway.. have fun. When she finally works you will feel an empty feeling. So just get yourself another challenge. Mend some more. Seriously... well done.

[scuzzb494]

Thanks all, I have no expertise in electronics at all, just got lucky with it maybe. I would have been lost if I didn't have the pcb explorer to tell me where the traces link, I printed a load of them out and checked one by one. 2 faulty is all I could find. I have used the vinegar, and cleaned with ipa, hope that's enough. Another update, the floppy drive isn't working. Tried a good clean of various parts and little oil on the motor screw, still no luck. Disk in, 3 ticks, then back to boot screen. May have to get an old one on ebay but not sure I want to spend 20£ on an old floppy drive! Madness!!

Did you neautralise the vinegar. I dilute my vinegar and then use liver salts [ Andrews ] which contains sodium bicarbonate. [ baking soda ] . Another use for these two items is to create your own mini vulcano. Mostly the combination turns to water in the form of bubbles. Dry very carefully.

Also return to your work on a regular basis to see if there is any further damage.

Problems are not just Amiga related by the way....

http://www.scuzzscink.com/amiga/scuzzblog_november17/scuzzblogdnovember17_1702.htm

http://www.scuzzscink.com/amiga/scuzzblog_november17/scuzzblogdnovember17_1704.htm

[scuzzb494]

The 1200 has an old seagate 2.5 210 mb hd, the a500+ is stock apart from the marpet 1mb expansion card. The joystick is a cruiser, it's as old as the Amiga. It took many a beating on all my games over the years, but still works fine!

I'm amazed that someone else has a Cruiser.... I call mine a Crusher or Bruiser

http://www.scuzzscink.com/amiga/scuzzblog_december17/scuzzblogddecember17_0901.htm

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