Troubleshooting a pair of A2000's

[Huxley_D]

Hi everyone!

Yesterday I bought an Amiga 2000 from a local guy for pretty cheap, as a companion to an A2000 I'd built up and then put in storage 7+ years ago. I pulled my original A2000 out of the storage locker today and have been playing with them both, but with unhappy results. Both machines still have their original motherboard batteries, and both batteries appear to have leaked at least somewhat onto the motherboard. The "new" A2000 has some visible gunk on the motherboard around the battery, while my "old" A2000 has quite a bit more (http://i.imgur.com/p36Wgfe.jpg). Setting that issue aside for the moment, here's the current situation with each machine:

1. My "old" A2000 is equipped with a Progressive Peripherals Zeus 040 (http://amiga.resource.cx/exp/zeus2040) board with an onboard SCSI hard drive and maxed-out RAM slots, and an Ethernet board in another slot. When I power this machine on, it comes right up (despite the battery leakage on the motherboard) but cannot boot from the internal drive - I get this odd error when it tries to boot (http://i.imgur.com/F42KJfZ.jpg). Given how much time has passed since I first set this machine up, I honestly don't remember if used to boot from the internal SCSI drive on the Zeus board or if I needed some sort of enabler floppy to boot. Any pointers here? The machine boots fine from a Kickstart floppy, but won't read the internal SCSI drive at all.

2. My "new" A2000 (http://imgur.com/a/R7RRc) is in rougher shape. It has a Genlock board, a Commodore-branded 2MB RAM board in one slot, and a GVP Impact 2000 SCSI + RAM board (http://amiga.resource.cx/exp/impact2000scsi1) in another, connected to some sort of very large (physically) SCSI hard drive in the HDD bay. Despite the seller having shared recent pics of it powered up and asking for a boot disk, I can't get any response whatsoever, other than the PSU fan spinning. I've tried reseating (and removing) the expansion boards, reseating the PSU cable, etc., but other than the PSU fan I can't get any sign of life. The Power light never comes on, the hard drive doesn't spin, and it never attempts to read a floppy (or even spin the floppy drive, as best I can tell).

Any tips on where I might proceed with either machine? I think it's fair to guess that my immediate next step will be to cut out those funky old motherboard batteries and try to clean off the battery leakage from the motherboards, but beyond that, I'm not sure. I suppose I could try transplanting the PSU from my semi-working A2000 to the totally-dead A2000, if that seems smart...

Thanks for any tips you might share!

[QuikSanz]

Send the best one to Acill in Oxnard and have him give it once over. Then have him look at the really bad one.

[Acill]

Send the best one to Acill in Oxnard and have him give it once over. Then have him look at the really bad one.

Uggg... 2000 and 3000 are not my favorite to look over. If its totally dead I may not be able to do a lot. Battery damage on the older machines are real hard to fix. They are mostly through hole components and have a lot of places that stuff can eat into traces and soak inside the boards from.

I would be glad to look at them both, and if you send them I'm sure I can salvage the good one that boots and take what I need from the bad one to save the other. Honestly with the price of an A2000 that works I feel its not worth a lot of effort to rework a dead one though. I would still have to charge you for my time and materials even if it doesnt work after an attempt. I usually stop at that point and tell people before it goes much over $150 of time.

[Oldsmobile_Mike]

I think with two systems you should be able to to get enough parts to make one working one. Get those batteries out and give everything in the area a thorough cleaning. You'll probably want to add a new hard disk or one of the various CF solutions instead of messing around with your old drive.

One other thought: acill's got a point about A2000's still being fairly cheap. If yours are both 4.x series boards I wouldn't sink a lot of time into them, look for a good working 6.x revision board, instead.

A2000's are almost always fixable though, good luck!

[Huxley_D]

Uggg... 2000 and 3000 are not my favorite to look over. If its totally dead I may not be able to do a lot. Battery damage on the older machines are real hard to fix. They are mostly through hole components and have a lot of places that stuff can eat into traces and soak inside the boards from.

I would be glad to look at them both, and if you send them I'm sure I can salvage the good one that boots and take what I need from the bad one to save the other. Honestly with the price of an A2000 that works I feel its not worth a lot of effort to rework a dead one though. I would still have to charge you for my time and materials even if it doesnt work after an attempt. I usually stop at that point and tell people before it goes much over $150 of time.

Thanks for the feedback and offer of help! I'm going to take some time this weekend to follow the general advice I'm getting here (and on Reddit too): tear down both machines, rip out the batteries, clean as much of the battery leakage as I can, and focus on getting the one that powers up to a bootable state. Ideally I'd like to verify that the expansion boards that came in my "new" A2000 (RAM board, SCSI + RAM board, GenLock board) are functional, and see if there's anything interesting on the SCSI drive that's in the "new" machine too. If any of those boards are worth anything, I'd like to sell one/all of them to recoup the cost of the "new" unit ($60) so I can at least tell my wife I broke even on this latest project :-)

I think with two systems you should be able to to get enough parts to make one working one. Get those batteries out and give everything in the area a thorough cleaning. You'll probably want to add a new hard disk or one of the various CF solutions instead of messing around with your old drive.

One other thought: acill's got a point about A2000's still being fairly cheap. If yours are both 4.x series boards I wouldn't sink a lot of time into them, look for a good working 6.x revision board, instead.

A2000's are almost always fixable though, good luck!

Good tips and feedback, thank you! As noted above, I'll follow your advice over the weekend and see if I can't get at least one machine to bootable condition. Definitely like the idea of swapping the increasingly-decrepit mechanical SCSI drive(s) for a solid-state solution, but maybe not before I see what interesting stuff might be on the drive in the "new" machine. Also, good point about the motherboards - my "old" A2000 (the one that's at least trying to boot now) is a Rev. 6.2, while the "new" one (that won't power up at all) is a Rev. 4.1

[QuikSanz]

Whoa, Stick with the 6.2 one and spare part the other for sure.

[Huxley_D]

Well, I think I might've found the problem with the "new" A2000:

http://imgur.com/oIQQhtS

Yikes!

What's the best newbie-friendly way to clean this up? I'm not gonna be crushed if this mobo is dead forever, but if nothing else I'd like to practice my battery cleanup technique on this board before I attempt the same on my mostly-working Rev. 6.2 board...

[Acill]

Well, I think I might've found the problem with the "new" A2000:

http://imgur.com/oIQQhtS

Yikes!

What's the best newbie-friendly way to clean this up? I'm not gonna be crushed if this mobo is dead forever, but if nothing else I'd like to practice my battery cleanup technique on this board before I attempt the same on my mostly-working Rev. 6.2 board...

Thats the CPU and at a minimum you need to pull it out and clean up those pins.

Go get yourself a big bottle of 99.9% of Iso NOT rubbing or store bought stuff, get 99.9 at least! You also need to get a bottle of concentrated lemon juice.

Brush on the lemon juice over the green areas and let it soak in good. Use an old tooth brush and scrub the effected areas off. Do it a few times if you need, its got to be done and it needs to get into all the problem leaking spots. you have a good chance of traces being damaged even more during this process, but you cant avoid it. Just do it.

Once it clean use the 99.9% Iso and scrub the entire board. Do be shy with it, clean everything. Scrub with the tooth brush (after you cleaned it out from the lemon juice) and be sure to get all the lemon out.

I like to use clean, non colored tissue paper. NOT the stuff you blow your nose with, the paper thats feels like the type you find in a public bathroom and goes over the seat. Take this and put it over the area you want clean. Take an acid brush and rub the Iso over that spot so the paper soaks up the crap under it. Use a clean piece for ever area until the board is dirt and contaminant free.

If you have canned air you can blow dry the board from iso in between cleanings too and again once complete.

Use a meter to find any open traces and a GOOD magnifier to find the once you cant see. They are there, trust me. Fix them with good solid core wire or a trace repair kit that uses copper foil and epoxy.

Its a long expensive process, but can be done.


Iso I use:


Lemon Juice:

[Huxley_D]

Thats the CPU and at a minimum you need to pull it out and clean up those pins.

Go get yourself a big bottle of 99.9% of Iso NOT rubbing or store bought stuff, get 99.9 at least! You also need to get a bottle of concentrated lemon juice.

Brush on the lemon juice over the green areas and let it soak in good. Use an old tooth brush and scrub the effected areas off. Do it a few times if you need, its got to be done and it needs to get into all the problem leaking spots. you have a good chance of traces being damaged even more during this process, but you cant avoid it. Just do it.

Once it clean use the 99.9% Iso and scrub the entire board. Do be shy with it, clean everything. Scrub with the tooth brush (after you cleaned it out from the lemon juice) and be sure to get all the lemon out.

I like to use clean, non colored tissue paper. NOT the stuff you blow your nose with, the paper thats feels like the type you find in a public bathroom and goes over the seat. Take this and put it over the area you want clean. Take an acid brush and rub the Iso over that spot so the paper soaks up the crap under it. Use a clean piece for ever area until the board is dirt and contaminant free.

If you have canned air you can blow dry the board from iso in between cleanings too and again once complete.

Use a meter to find any open traces and a GOOD magnifier to find the once you cant see. They are there, trust me. Fix them with good solid core wire or a trace repair kit that uses copper foil and epoxy.

Its a long expensive process, but can be done.


Iso I use:


Lemon Juice:

You are a fantastic resource - thank you for the detailed instructions! :-)

[apsteinmetz]

Speaking from firsthand experience, that IC socket is toast.  Pull it out, then clean everything up.  Check trace continuity.  Put a new socket in. Check for shorts.  Clean 68000 leads and plug back in.  That worked for me.

[Huxley_D]

Well, here are the results of my first pass at cleaning the "new" A2000 motherboard of the battery gunk:

http://i.imgur.com/c5Qmu6N.jpg

I'm gonna keep at it and see how it goes. I'm a complete novice when it comes to soldering, so I fully expect to completely destroy this mobo by the time I'm done, but hopefully I'll learn enough that I can do some actual good when it's time to attempt the cleanup on the "good" Rev. 6.2 board.

If (as was already suggested) the 68000 socket itself needs to be swapped out, other than locating a suitable replacement, are there any guides or tips you guys can point me toward?

Thank you all again for your continued suggestions and guidance here - I really appreciate it!

[QuikSanz]

Well, here are the results of my first pass at cleaning the "new" A2000 motherboard of the battery gunk:

http://i.imgur.com/c5Qmu6N.jpg

I'm gonna keep at it and see how it goes. I'm a complete novice when it comes to soldering, so I fully expect to completely destroy this mobo by the time I'm done, but hopefully I'll learn enough that I can do some actual good when it's time to attempt the cleanup on the "good" Rev. 6.2 board.

If (as was already suggested) the 68000 socket itself needs to be swapped out, other than locating a suitable replacement, are there any guides or tips you guys can point me toward?

Thank you all again for your continued suggestions and guidance here - I really appreciate it!

Been soldering since I was 8, lots of electronic classes but not in soldering. Pretty much Mil Spec now.

A good soldering iron, I use Weller at work with adjustable temp, and one of those blue nylon spring loaded solder suckers will do wonders. 1mm solder is also good.

[Acill]

It doesnt looka t bad as I expected. But take your time with it. Remove the socket by heating a ping, add a very small bit of new solder until it blends with the old. A SMALL AMOUNT! Take a GOOD SUCKER SUCKER. The brand name ones with a blue body and a yellow plunger end. Heat the new solder you put on the pin and while the iron is still on and solder is molten hit the release and suck it off. Repeat with existing solder, dont add more. Hit it a few time with that sucker. Use some solder braid and lux to pull the rest out and repeat with the rest of the pins. Its a slow process and takes a lot time if done right.

Solder sucker to use:
http://www.digikey.com/short/34q9b2

Solder Braid to use:
For the pin holes once out: http://www.digikey.com/short/34q9bn
For the stuff on top as you remove: http://www.digikey.com/short/34q9b0

Solder I like:
http://www.digikey.com/short/34q95t

ESD Tweezers straight:
http://www.digikey.com/short/34q958

ESD Tweezers Curved (Not cheap, but these are my workhorse tweezers
)
http://www.digikey.com/short/34q95b

[QuikSanz]

Yup, that's the solder sucker I use. Solder removal braid works best on SMD but is useful with thru hole stuff in a pinch.

[spaceman88]

I'm surprised they still sell these solder suckers, looks just like mine.  I got mine at work 25 years ago. We used them for quick jobs when it wasn't worth turning on the big "central vac" system. We would be done the small jobs before the big system got heated up. I just used it yesterday changing a couple of capacitors in a Dell monitor/TV.