Amiga 1200 maintenance after 20+ years in attic

[highwinder]

Hi everyone,

Just dusted my Amiga 1200 off from 20+ years in the attic, I was amazed it still works!

Can anyone recommend any necessary maintenance that I could do to extend it's life further? Any batteries that can be easily replaced or capacitors that could be easily checked?

I've zero experience in any of this so more details the better, but can work with a soldering iron if needed!

Thanks in advance

[talybont]

It is common practice to replace all electrolytic capacitors.

[demolition]

20 years in storage means that the electrolytic capacitors will very likely be bad by now. While they may look fine right now, it is quite common to see them starting to fail very quickly after the Amiga is powered on again after being in hibernation for such a long time. When they dry out, the leakage current increases so they start to run very hot and whatever liquid is left inside will start to leak out over the motherboard.

So don't be surprised if it fails to boot in the near future unless you have it recapped.

[talybont]

This page has a list of the capacitors and their values:

https://www.ikod.se/repairs/capacitor-lists/

And a handy map with their location on the motherboard:

https://www.ikod.se/amiga-1200-cap-map/

[gimbal]

A youtube search for "Amiga 1200 restoration" will likely net you some very valuable results that can help to show how you need to do certain repairs. I'm a complete idiot when it comes to electronics and even I can follow those videos, usually. If you see one then the Youtube homepage just keeps on suggesting more of such videos, and I keep on watching them.

Of course for me it is mostly hardware pr0n, I wouldn't dare to touch a soldering iron...

[demolition]

I wouldn't recommend anyone to recap an A1200 themselves unless they are experienced in soldering SMD. If you don't do it right and isn't careful, it is easy to lift a trace on the PCB and then you are looking at a much more problematic repair.

[alexh]

My Amiga was in storage for over 20 years, is now powered on at least once per week for 2-3hrs. Hasn't been recapped. Everything still works. No obvious sign of leakage.

You're 1 million times more likely to break your A1200 irreparably by trying to replace caps yourself than leakage.

Get it done by a (semi)professional. Or wait until the early signs.

[demolition]

Originally Posted by alexh

Get it done by a (semi)professional. Or wait until the early signs.

Early signs being dull looking solder on the pins of the caps, so one should check regularly to make sure it still looks fine. At least once a year I would say. When the Amiga starts acting up, doesn't want to boot etc., that would be the late signs and the caps have probably been bad for quite a while.


And yes, you can always find exceptions with machines that are still running and looking well today with 25 year old caps but that doesn't change the fact that a lot of A1200s are suffering from these problems.

[nexus]

just remember temperature can make a cap seem ok when it isnt
this is why we use a can of CO2 and freeze them when trying to determine if they are bad
so yeah i have a a1200 from dave haynie works fine i havent recapped it yet but doesnt mean that it doesnt need it
those caps could be way off there ratings and another cap could be taking on the extra duty etc

[rare_j]

Yeah I used to get all my consumer electronics straight from Dave Haynie as well. Not only home computers, he also had a lock-up full off walkmans and knock-off rolexes as well.
My man Dave always sorted me out for all that stuff.

[nexus]

https://www.bigbookofamigahardware.c...uct.aspx?id=13
never seen rev 1D
was actually his mothers
had him sign it also

[Daedalus]

Being way off their ratings in itself isn't going to cause you massive problems except in the case of capacitors in the audio path. It's the leakage underneath them that causes serious damage. Especially if the board is of significant sentimental value (e.g. rare revision or signed by Dave Haynie), I would be worried about invisible damage beneath the capacitors.

[highwinder]

Thanks everyone for the comments!

[nexus]

smd caps arent like huge barrels of acid like those varta batts were and not as corrosive
but it will be capped soon i just been using it to save floppies of mine lots of artwork i did as a kid

i need to grab another a1200 board just cause i dont wanna do modding to it
case wasnt yellow either i had him sign right above amiga logo and inside the amiga

he threw in some of those nice diamond cut case amiga badges too
was the 1st amiga i bought few years ago when getting back in when dave was selling lots of stuff on ebay
same time he sold the NX boards

[Daedalus]

Indeed, they're not, but they're big enough to hide the damage they cause to the tiny traces that pass underneath them. Having repaired dozens of 600s and 1200s with that very issue, I can tell you that it's not always visible, and doesn't have to be a large area to stop the machine from working.

[project23]

I recently (this year) bought these for my A600:

https://www.ebay.co.uk/itm/AMIGA-600-A600-COMMODORE-Re-capping-Capacitor-Kit-HIGH-Quality-PANASONIC-CAPS/162583605668?epid=26016018236&hash=item25dabcf1a4:g:tEoAAOSwY4pZYQek:rk:1f:0

I was really impressed. Nice little eBay startup there. They even sent me a colour printed diagram of the A600 motherboard with the caps colour coded and labelled.

That is, if you're taking it on yourself. If you're not - then maybe buy them (for the A1200 of course not the 600) and take them to an electronics repair shop and ask them to do it. I'm not sure if you'll save money on parts, but you probably will on quality.

John

EDIT: Here's your A1200 ones... They have a website somewhere too...

https://www.ebay.co.uk/itm/AMIGA-1200-A1200-COMMODORE-Recapping-Capacitor-Kit-HIGH-Quality-PANASONIC-CAPS/162550198375?hash=item25d8bf3067:g:K84AAOSwq~tZPaxv:rk:11f:0

[project23]

Originally Posted by highwinder

I've zero experience in any of this so more details the better, but can work with a soldering iron if needed!

Does this mean zero experience in Amiga repair/maintainence or zero experience with an iron?

If you have the proper tools, do it yourself - it's really easy. By proper tools I recommend an air gun (soldering station, air blower, you know what i mean - and I know i'll get people disagreeing with this) - but you absolutely have to do it properly. Set the temp to the lowest you can to melt the solder, and use a nozzle the same size (roughly) as the cap. Aim the nozzle at the capacitor itself, not the pads individually. It'll take a longish time (because of the relatively low air temp), but eventually it'll slide off with minimum effort (a slight nudge with a needle, say). Obviously cover the thing in flux etc AND WEAR SAFETY GOGGLES.

Then use wick to remove the rest of the solder from the pads. Give it a clean in IPA and put the new ones in place however you find most comfortable to you. I did not use a gun for this. I added a small amount of solder to each pad, placed the cap, and soldered each side gently (read: low temp slow or high temp quick) until it flowed properly.

No problems since, and no problems with the pads or damage to the board (Except when removing the modulator but thats another bloody story )

Do not under any circumstances use the 'tried and tested' method of twisting the old caps off with pliers. Go watch some youtube videos of this failing miserably. Some people swear by it, and you might get lucky, but probabilistically speaking you WILL TEAR OFF A PAD.

Okay back to work now, peace!

John

EDIT: If you're worried they may have leaked a little, then a cotton-swab wash with lemon juice will neutralise the battery 'acid' before the IPA wash. If using a gun to remove the caps, then as they heat up if you smell a fishy sort of smell then they've leaked. I can't stress how easy this process was for me any more than by saying the through-hole caps (which you'd imagine would be easier) were the hardest for me to remove.

[dlfrsilver]

hot tweezers allow to do the job very safely, you heat both sides of the pad, and that's it !

Just need to clean up carefully them

[project23]

Originally Posted by dlfrsilver

hot tweezers allow to do the job very safely, you heat both sides of the pad, and that's it !

Just need to clean up carefully them

Do you have Teflon hands or something?!

[highwinder]

Originally Posted by project23

Does this mean zero experience in Amiga repair/maintainence or zero experience with an iron?

Zero experience with Amiga repair but have some experience with an iron. Will open it up and see how its all looking, thanks for the tips. Those kits do look simple enough, just have to take it slow and steady!