Amiga.org
Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: 98PaceCar on July 30, 2003, 12:29:09 AM
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Hi everybody,
I'm a newbie to the site, but I used to be a hard core Amiga user back in college. I had recently pulled my 500 out and started playing some of my old favorites and remembering the good times! As luck would have it, I ran across a mostly working 3000 for $20 last weekend! Once I got into it though, I found that the battery had started to leak.. Not good. I've used a mix of 50/50 vinegar and water with a small nylon brush and got most of it off. It left about a quarter size spot on the mb where the copper is exposed.
The system seems to still work, but whenever I try to boot off the hard drive, there is an assign that is failing. I'm assuming for some reason one of the two hard drives is not working, but was wondering if there is something around the battery that could have been affected that would cause this.
I've been able to boot off of a floppy with no problems. The mouse and everything seems to work ok, no keyboard yet, so I can't test that part unfortunately.
Also, is there anything special I should do to the spot where the acid ate through? I'm going to clean it again with the vinegar/water mix and see if I can get the few tough spots off. I've noticed a bit of damage under the one resistor that is on the negative side and a little bit had started to creep up the one TTL chip that is right past the resistor (can take a pic if needed).
Anyway, I'd appreciate any advice I can get. I'd love to get back into the Amiga with what used to be my dream system!
Thanks,
Darren
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Try using a little baking soda mixed with a little water to make a thin paste instead of the vinegar. The baking soda will neutralize any acid on the board. Rinse as well as you can with maybe a cotton swab and water. Let air dry for a couple of days, or use a blow dryer on low. I think the coating on the board is just a type of laquer, might be able to find something similar in an electronics supplier catalog. If everything seems to work, maybe the board is ok and there is something in the startup sequence? How you get it going real soon. Regards...Art
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The previous tip about the baking soda is righton target. After the baking soda clean the board with alcohol or some sort of contact cleaner. Not tuner cleaner as it has a lubricant. The coating on the board ( called a conformal coating) is either polyurethane or an epoxy resin. If you want to recoat there are conformal coatings in spray cans available from electronics supply houses. I repair boards regularly without replacing the coating though.
Hope that helps.
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Welcome back Darren,
You didn't mention if you replaced the battery. I replaced mine with a rechargable phone battery encased in plastic from Radio Shack. The wire leads are soldered to the old battery pads (observe polarity) and the new one just lays on the motherboard. You probably know this already, the voltage of the new must match the old, the mAh rating is flexable.
If you check the motherboard from time to time to ensure the corosion has been halted, all should be well.
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Thanks for the advice guys. Do you think the vinegar/water mix has harmed anything or is the baking soda just a better solution? I don't think I'll worry about recoating the board. Hopefully I won't be spending much more time in the case and more time actually playing with it!
Hoping it is just a config problem. Not having a keyboard makes debugging a real nightmare, but I'm working on getting a hold of one as quick as I can!
Thanks again,
Darren
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I tell you, it's nice to be back! I had forgotten how much I liked my old 500 till I drug it out. Now I can't wait to get the 3000 going so I can have some real power!!
I just hit rat shack today and picked up a portable phone battery. I've done that trick on a few classic arcade games I've restored. Works like a champ there so I figured it would be fine here as well. Thanks for verifying for me!
Darren
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The system seems to still work, but whenever I try to boot off the hard drive, there is an assign that is failing.
i think some of you have probably missed the probable cause here
go through your startup-sequence or especialy the user-startup and look at what might be there that shouldnt, or what might be missing
:-)
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It's that time of year again guys, check your AMiGA's battery!
A leaking battery can kill your AMiGA.
A few members here have said about AMiGAs stored away, remember to
check them too.
@Darren,
Good luck with your 3000, my battery had leaked like you describe when
I got it years ago, I cut the battery off and cleaned the motherboard
and components with a small amount of CRC 2.26 electrical cleaner on a
cotton bud (Q-Tip).
I have been without a battery since. The A3000 does not need it to
work. Hopefully the components are not damaged.
You will need
Aminet SetBatt (http://uk.aminet.net/aminetbin/find?setbatt)
to reset some system settings that the A3000 has stored when powered
off.
For the ASSIGN that is "missing", you say you can boot off floppy.
Can you see the harddrives on Workbench?
You will need a keyboard to fix the problem though! A A2000 one will
work.
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I'm sure hoping it's just a simple config issue. It's been a LONG time since I've looked into the setup on these things, but I've still got a set of WB 2.1 books and a lot of extra time on my hands!! :-D
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Miles,
What kind of settings will I have lost? Anyhing related to SCSI setup or anything like that?
Fortunately, I was able to find my copies of the 2.1 WB install disks, so I should be able to boot from those. Do I need a special version of WB for the 3000 or will the disks I have work (I bought them when I upgraded my 500 to 2.04 roms with a switcher)?
Thx,
Darren
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There is NO acid in a clock battery! Do NOT use vinegar or baking soda on your motherboard!
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Ok, so no vinegar or baking soda (even though it's too late on the vinegar, which did remove 95% of the damage the leak caused). What do I do then? I'm not letting the damage continue when I've got a working 3000 mb sitting here.
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NEVER use baking soda, vinegar or any other acid substance on any circuit board!
The best thing to do is use Isopropyl alcohol to neutralize the battery acid. Use a toothbrush to get in hard-to-reach areas.
Then rinse the board with 50/50 alcohol and water.
ANY damaged semiconductor must be removed and replaced to prevent further occurrances with battery acid.
If you know electronics, use a multimeter to perform continunity tests. Any bad trace is considered useless and new traces must be soldered. If you do not know how, send the board to an Amiga repair specialist. Yes, send the pic to me.
Hope this helps.
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You need to get all of the battery fluid off your components. It's soluble in polar solvents like water, but try not to use water (the water in the vinegar took it off before, not the acetic acid itself). Pure alcohol, or even better, isopropyl alcohol or circuit cleaning fluids, will take it off best. If you don't have any of this you can use a little clean water on a cotton bud. Just dry it as soon as possible.
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@KennyR
===ALL=== batteries carry acid except memory capacitors. Memory capacitors are THE next best thing to replacing batteries.
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@Dandude
===ALL=== batteries carry acid except memory capacitors. Memory capacitors are THE next best thing to replacing batteries.
No they don't. Only lead-acid batteries such as car batteries have acid inside. In fact, many batteries are alkaline, not acid. Ni-Cd batteries like those used in most older clock "coin" batteries actually have sodium hydroxide as an electrolyte, a powerful alkali.
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Ok, I've got some isopropyl alcohol at home, so I can re-do it with that. I don't think any of the components were damaged, but until I get it all back together I won't know for sure. The damage is pretty much isolated to the negative side of the battery and the surrounding area where there isn't too much to damage.
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@KennyR
OK, acid or not, they still contain harmful effects that can destroy the board, right?
http://www.lightuptheworld.org/environmentbattery.html
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Dandude wrote:
OK, acid or not, they still contain harmful effects that can destroy the board, right?
Sure. They do to your circuit boards what they should be doing inside the battery - reacting. Most real acids won't attack copper or lead-solder anyway. ;-)
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KapitanKlystron wrote:
The coating on the board ( called a conformal coating) is either polyurethane or an epoxy resin.
I don't think C= had any boards conformal coated. It can be expensive to conformal coat a large board and it's not needed for home electronics. It also makes repairs a real pain. From what I remember working in electronics manufacturing, the top and bottoms of PWB's are called laminates. When these layers are gone or have detached from the PWB, the boards is said to have delaminated.
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Darren,
The A3000 keeps it's SCSI settings in battery backed up memory,
setbatt can restore these settings.
They are:
SCSI Preferences,
Long SCSI Timeout (Seacrate Mode)
Synchronous Transfer
Support Multiple LUNs
Host Adapter
It might happen that you need to reset these, if I power off my A3000
I have to reset SCSI Synchronous Transfer. This does not stop my
A3000 from booting though.
For Workbench, what ROMs do you have?
The A3000 has 3 types. 1.4 boot roms that softkick a rom image from
hard drive, 2 roms that do not need a hard drive installed rom image
and 3.1 roms, which I have and is the best option.
Workbench 2 will install on 2 and 3 roms, boot from floppy and use
hard drive toolbox to set your hard drive if needed (you can just copy
the boot floppy to hard drive and change s:startup-sequence and
user-startup to point to hard drive insted of floppy, if needed).
With 1.4 roms you will need to set your hard drive up with hard drive
toolbox (from your install disks), call the boot hard drive partition
wb_2.x in hard drive toolbox and set the drives boot partition to
FFS with out DC or international checked. Your KickStart image should
be in DEVS: This is because V.36 boot roms boot the machine and look
for a hard drive called wb_2.x to find a kickstart 2.x or 3.x rom
image then reboot using the hard drive kickstart. The kickstart
image must be for a A3000.
Have a look at my website, it is about the A3000. Feel free to email
me :-)
Others:
CRC 2.26 (or another electrical component cleaner) works wonders for
cleaning the white gunk from a leaking battery off your computer.
Wiped it once years ago, no gunk "growback". We used this (crc 2.26)
to clean the white gunk off telephone terminals on telephone poles
(the spiders did not like it though!). It works, is safe, does not
contain a lube like crc 5.56 or wd40 does and you can keep the rest of
the can in the car for battery terminals etc. :-)
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@N7VQM
You are right about that I took a look at my A2000 motherboard and It was not coated. I guess force of habit from working on military and industrial circuit cards. Your'e right about coatings making repairs a pain. Sometimes you spend more time removing and replacing coatings than resoldering. :-)
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Miles,
It's a revision 9 motherboard and I do remember seeing 2 roms that were labeled 2.04. So it looks like I will be ok to boot from the floppies I already have!! Hooray!! Now I just need to hold out till my keyboard gets here (it's in a fedex truck right now) and I'll be in business!
On a side note, I decided I should pull the 501 cards out of both of my 500's, just in case. Sure enough, they are furry too... :-o
Looks like I've got some more cleaning to get done!
I'll check out your site. Thanks for the info!
Darren
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Darren,
2.04 is good! When I got my A3000 I had 1.4 softkicked to 3.1 (I
had a A1200 before that) and I changed my boot partitions name to sys
as I thought wb_2.x looked "messy", took a while to figure out why it
would no longer boot!
The 501s I have are furry as are old 486s, those batterys were a bad
idea :-(
Going through a major rework on the site, been really busy lately!
Finally got some spare time now :-)
Got shapeshifter on the net and am setting up networking to a pc (for
deathmatched doom and quake) that is serial linked to a A600, that
will (when I can find a cheap one) be parnetted to a A1200 for AGA
only games.
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Miles,
Awesome! Some good news finally!!
There's some great info on your site. Now that I'm home, I'll have to surf all of it. Thanks for pointing me in the right direction. I completely missed the obvious link to your page. I guess it was too obvious!!
Darren
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DanDude,
I just put some pics of the damage out on my pic site. They are kinda big, but you can see all the damage in them. If they are too big, let me know and I'll resize them.
www.pbase.com/darrenes/a3000
Thanks for your advice! I used some isopropyl alcohol on it when I got home. I've wiped it all off and am just letting it sit for a while before I do anything else. I'll probably hit it with a blow dryer on no heat to blow out anything that's left later.
Oh yea, the pics are after I used the alcohol on it.
Thanks!
Darren
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Make sure u stay grounded as not to short out anything (else) on the mb. Also when u are done cleaning up the spill make sure u cover the bare copper. They have a green cover liquid that u can go buy at a electronics store for it, forgot what it was called tho (brainfart:).
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no problem!
:-)