A500 worth saving?

I recently got the Amiga bug again as having kids has reminded me of the fun I had with Amigas and C64s back when I was young. Having an A500 I bought nearly five years ago I pulled it out of the shed. To say the years have not been kind to it is probably a bit of an understatement. I brought it into work where I had some space and pulled it apart to see what the damage is like. Those of you with weak stomachs look away now (j/k ):

The outside looks dirty and yellowed (as expected) but otherwise OK. It turns on and reads disks. Full gallery here: http://imgur.com/zGERRPO

The fully assembled 500. It will turn on and read disks happily.


The power supply is in fantastic shape and makes no worrying noises (not sarcasm):


Here's where things get a little bad, inside the top of the case:


The bottom of the case, this doesn't look good at all:


A large amount of rust on the shielding:


Without this piece of plastic I think this Amiga would be DOA:


The extent of the rust on the motherboard was limited to the connectors. The joystick ports and RGB port still work. No idea about the others as I don't have peripherals for them.



Luckily the motherboard appears otherwise undamaged. No burst batteries or caps:


Floppy eject button hanging on by a thread:


The dirty but otherwise fine keyboard:



Thanks for looking at all that. What I'm hoping for is that there is someone in Australia (preferable in Melbourne or at least Victoria) that can clean, repair, and recap this old beast. Then I'll need a RAM expansion (I believe I have one but that looks like it is not in fantastic shape) and some better way of getting video than the A520 with composite output. You have to jiggle it to get all the colours on-screen and I'm hoping that it's the A520 at fault and not the port.

I'm obviously willing to pay, unless the price would be so high I would be better off buying a "new" one. Or do people think I'd be better off saving my pennies and springing for an A1200 from eBay?

[demolition]

The bad video would likely be due to corrosion in the connector since it clearly suffered some water damage. Recapping is not required on A500s and there is no battery deal with, so these are easy to maintain. I would start with a good clean and take it from there. If some of the connectors are too far gone they will need replacing and that takes a little work with a soldering iron (and the 23p connectors can be a little tricky to find since they are not commonly used any longer). You could probably make it work well enough though if you just gave it some contact spray and plugged/unplugged a connector several times.

I usually clean a motherboard by giving it a run in the dishwasher. It really does wonders and can make a crusty dirty one look almost new. It probably won't take the rust away though.
I use a quick-cycle which is 30 minutes on low temperature. Immediately after this I take it out, rinse it with demineralised water and stick it in the oven on low temp (around 75degC is good) for a couple of hours to dry. I would do it with all ICs removed, clean those manually with isopropylalcohol and reinstall them after the motherboard is dried and ready to go again.

For the rust on the shield, you can take it off with some sanding paper and cover it with a clear coat laquer. Alternatively you can use a rust converter to stop it from developing. It will turn the rust black so will not look perfect but otherwise it works great and is very easy to use since it can be applied with a brush.
https://en.wikipedia.org/wiki/Rust_converter

Good to know I don't need to worry about recapping or anything. I will give your dishwasher method a try. Silly question, should I put detergent in or just rely on the hot water to do the job? Would it be ok to put the case in there too or is that risking warping it?

As the for shield, I'm not too worried if it goes black so rust converter will be the way to go there.

As for the video output hopefully I don't need to replace the connector, but first I need to get a scandoubler so I can connect it to a monitor. When I was testing today I couldn't find a composite cable or a TV, so I cut the end off a 2xRCA to 3.5mm cable and spliced the RCA ends together, then plugged it into a spare projector. Funnily enough this worked wonders!

Thanks for your help, I'll be sure to report back with the results. I'm also happy to hear any other suggestions people have.

[demolition]

I always use detergent and I stick the case parts in there as well with the outsides facing down, although in a way so they don't capture too much water. Breadbin C64s can become (more) miscolored after being in the dishwasher, but I've never had issues with Amiga cases or C64C cases for that matter and I've done quite a few that way. If your machine can keep the temperature low enough (I think mine's 50 degC), that will not cause any warping.

The only minor issue with the are that any paper stickers might come off. Your case might have one on the bottom and the motherboard usually has several as well. The glossy ones are usually fine, but the paper ones will absorb water and disintegrate either completely or partly. If this is an issue (it isn't for me), you should probably wash it by hand.

Cool, I'll see if I can't confuse my wife tonight.

[demolition]

I don't know if it was clear, but keep the floppy drive and keyboard away from the dishwasher. They should be cleaned manually.

[Predseda]

I have seen much worse Amigas. This one just needs some cleaning, thats all.

[Signman]

If you have some special attachment or want to immerse yourself in a project, go ahead.
Otherwise, these 500s are cheap to buy.

[obitus1990]

I wouldn't go so far as to say the a500 doesn't need recapping. One of my A500s started leaking from one of the TH caps, evidenced by corrosion on a nearby component, so, it got recapped. John Hertell also says this is a myth, as he too has seen A2000s with leaky caps.

No special attachment, but I don't see them go for any less than $100 in this neck of the woods, so I'll see what sort of revival I can do to this one first and hopefully put that cash towards an accelerator card like the ACA or maybe a Vampire.

Thanks for the word on the caps, I'll just have to cross my fingers at the moment.

[Predseda]

Originally Posted by kirk_m

I wouldn't go so far as to say the a500 doesn't need recapping. One of my A500s started leaking from one of the TH caps, evidenced by corrosion on a nearby component, so, it got recapped. John Hertell also says this is a myth, as he too has seen A2000s with leaky caps.

Sure. But at least in A500s the dangerous capacitors are clearly visible. Unlike A600/1200, where the leaking uses to be hidden.

[demolition]

Originally Posted by kirk_m

I wouldn't go so far as to say the a500 doesn't need recapping. One of my A500s started leaking from one of the TH caps, evidenced by corrosion on a nearby component, so, it got recapped. John Hertell also says this is a myth, as he too has seen A2000s with leaky caps.

Ok, I guess there are always exceptions but you are the first one I hear from who has experienced leaking caps in an A500 first-hand. But I guess it should be easy to spot since the caps will be bunging at the top unlike the SMD caps in an A600 and 1200 which just leak from the bottom.

[ElectroBlaster]

I am amazed it even works! I would be attempting to clean the ports up or if not, having them removed and fitting good salvaged ones on.

I would save it! I have a serious problem with taking in abandoned and mistreated A500's. I have one with a smashed up Agnus socket. There was no reason at all for me to buy it, I just jumped on it after the typical owner who went in with screwdriver and got moody. I saved it and will replace the socket. The board is spotless apart from that little scab

Also I bought an early german "chicken-lips A500" recently. I have not done much with it but I suspect all is not what it seems, I am aware it does not work but I have a suspicion the board is not what was detailed
The cinch connectors do not add up with a revision 5, but more of an revision 8!

The case and keyboard were worth it alone mind! has the early mechanical keyboard, early-low serial number so I can probably re-create an early 500 that kind of thing.

[ReadOnlyCat]

In addition to the demineralized water I would also use 99% isopropyl alcohol on the board after the demineralized water.
This will help evaporate the water which might be lodged under supports or components.

Do not think you can skip the demineralized water, this is essential to remove any remaining minerals which might restart corrosion of the board. I would even advise to use a toothbrush to spread around the water everywhere (use a new one or you will add more unwanted deposits).

So to recap: dishwasher, brush with demineralized water, rinse with demineralized water, rinse with isopropyl alcohol (do it outside and away from any flame or electric device), let evaporate a few minutes then oven for a few hours.



Looking at the pictures I would think you will have to replace the connectors, if they are still rusty after all that it is better not to risk any future corrosion and replace them. Better safe than sorry.

Thanks for reminding me of the demineralised water, I will need to pick some up. Haven't had a chance to get on this yet, so much other stuff on the go! I've also being eyeing off eBay auctions and deciding if I hate my savings enough to splash out on an A1200 for that sweet sweet AGA action.

[demolition]

Regarding the alcohol, it depends on how you intend to dry the board. If you use an oven to dry the board like I do, then I don't think alcohol is needed and actually I wouldn't stick an alcohol-soaked PCB into a hot oven.

If your oven cannot go low enough to avoid damaging the board (75 degC or so) and you need to dry it at room temperature, then washing the board with isopropyl alcohol can be a good solution since water on its own will take long to evaporate. In a 75degC oven for just a few hours, close to 100% of the water should have evaporated and if the water is demineralised/distilled, then there will be no deposits remaining. The heat will make sure that all the water is evaporated quickly, even inside various cavities.

Incredibly belated trip report: it's cleaner, but I made it worse.

It now won't read disks. The floppy drive makes a few noise and the screen goes blank for a moment, but then goes back to the insert disk screen. I've tried all the orientations of plugging in the floppy cable just in case I did it wrong reassembling it.

I also discovered I forgot to remove the 1.3 ROM before I put the board in the dishwasher. I'm wondering if this is related to my disk loading problems. I have a spare ROM that I will try inserting but having just spent two hours putting it back together I couldn't be bothered for the moment.

[demolition]

Originally Posted by chiefnewo

It now won't read disks. The floppy drive makes a few noise and the screen goes blank for a moment, but then goes back to the insert disk screen. I've tried all the orientations of plugging in the floppy cable just in case I did it wrong reassembling it.
I also discovered I forgot to remove the 1.3 ROM before I put the board in the dishwasher. I'm wondering if this is related to my disk loading problems. I have a spare ROM that I will try inserting but having just spent two hours putting it back together I couldn't be bothered for the moment.

Having the ROM inserted should not be an issue. Just remove it and reinsert it and it should be good.
I'm sure your current floppy issues are not caused by the ROM. When the KS screen disappears for a sec and then reappears after inserting a disk, that means that the Amiga did recognize that a disk was inserted, thus the cable is correctly orientated. It just could not read the contents which is usually due to either trying to load FFS formatted disks with ROM 1.3 (they only work with KS2.0+), the disks could be bad, or the drive heads needs a cleaning. Old floppy disks can have mold on them which will deposit on the drive heads, so trying to use such disks will quickly render the drive non-working.

Yeah, wasn't the ROM as you said. Turned out to be a dicky eject/insert mechanism exacerbated by the tape I put on to make the half broken eject button stay on properly. After I fixed that it now reads fine. Although it appears the power supply is flaky as a jiggle of the cable at the supply end will make the screen fizz for a moment.

My A520 also still has the greenish hue to it unless you give it a bash or manage to lift it to just the right spot. I've ordered a better SCART upscaler to go with the RetroShack RGB->SCART cable I got as my current el-cheapo upscaler doesn't actually show a picture.

I think I can consider this a good starting point for spending some more money, thanks everyone for all your help getting me this far!

[B14ck W01f]

Originally Posted by chiefnewo

What I'm hoping for is that there is someone in Australia (preferable in Melbourne or at least Victoria) that can clean, repair, and recap this old beast.

You can contact Paul De Piazza, who has his workshop in Ballarat but is prepared to go as far as Warragul. He was able to restore my dying A1200 for $65. You can contact him at pdepiazza@gmail.com