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[DaBest]

Sheesh......
I am just wondering what battery the seller was talking about when he stated "no problems with the battery".

Maybe the motherboard has other batteries that we don't know about.
Good luck.......hope things get better then worst.

PS.....Yank that puppy out ASAP

[alexh]

Most barrel batteries are NiCd. The electrolyte in NiCd batteries is potassium hydroxide, an "Alkaline".

To neutralise it you should use use a weak acid. Vinager or Lemon Juice.

[da9000]

jiminy wrote:
Can the battery actually leak all over like that, or is this the result of someone's attempt to clean it?

Typical leakage. Nobody seems to have tried cleaning it. This is how my A3000 died :-(

jiminy wrote:
Another issue, the screen has streaks in it. It seems to diminish as she gets warmed up. I thought the A3000 had a fine tuner for it's flickerfixer? Is it software? I can't find a knob.

It sounds like a symptom of the leakage, but try the trimmer in the back and see if that takes care of it. If it does, consider yourself lucky, because if it's the leakage, who knows where the problems are.

I'm with AmiGeek on what he says. Now, I might not totally endorse the swap mobos right away, but it's very likely you'll need another in the future. Mine died YEARS after having cleaned a much smaller leakage! So if you find a good one, get it for spare parts.

And lastly, for cleaning, search the forums, there are many great threads. One came up recently with photos, but read the commentaries as there were some grave mistruths, such as the stuff leaked being an acid. As AlexH says, it's NOT acid, it's alkaline material.

Good luck with your A3000! They were great machines!

PS. Two questions: how much did those static page ZIPs go for? And who's the seller on ebay, so we can protect ourselves from liars (or in case he really didn't know the blue barrel thingy is the battery, clueless sellers)

[amigaksi]

>Another issue, the screen has streaks in it. It seems to diminish as she gets warmed up. I thought the A3000 had a fine tuner for it's flickerfixer? Is it software? I can't find a knob. Sorry to be so stupid, my only Amiga was an A500.

Those streaks are the result of battery leakage affecting your Denise to video output path. You can't fix it with any knob on the Amiga 3000. Try presssing the Denise chip slightly while viewing and you will see the patterns change or even go away. Removing and cleaning out the Denise may help get rid of it as either the contacts are not being made properly or worse some trace is hardly making contact and the sync pulses are being thrown off. Hopefully, it's just the way the Denise is making contact with the socket.

Hopefully, other traces/contacts related to video circuitry are not affected and you may be able to put in a video card into the video slot that does not use the Denise output (like Magni boards) and use that for video output.

[Tenacious]

I would think you could neutralize that without too much trouble. You can always pull the battery from the MB, disect it, and test vinagar, baking soda, etc on it before attacking the MB. Simply be thorough in scrubbing out all the crannies and especially drying everything before powering up. I would be tempted to solder-in any unfilled through holes to other layers. The flux may provide further cleaning and the solder may keep oxygen out, preventing further corrosion.

It looks like you are testing the system with a LCD monitor, I would try a 31 kHz CRT before drawing any conclusions about the video chips on the MB.

Rescuing rare equipment is a good thing.

[jiminy]

Looks like y'all are right. The blue stuff is in almost all the pins on the near side of Paula and in several pins on Denise. I'll look through the threads on cleaning... I don't have a toothbrush that small! I wonder if people eventually losing their Amigas even after cleaning is not so much due to the cancer being unstoppable as just not being able to get to it all.

da9000, the static zips were $135. The page mode were actually more, being they were 60ns versus 70 for the static. It's not a cheap hobby... I don't want to call the seller out. But there weren't too many A3000s with only 1M ram sold for over $300 recently, if ya know what I mean.

Thanks for the expert help.

[jiminy]

Well, I'm going to give it a shot... I did hook it to a crt and the streaking was gone, but that's where I'm seeing the odd yellowish pattern, where there shouldn't be any yellow. Also, even on a 640x200 screen, there's some random pixel frying going on.

Tomorrow's another day...

[DigitalQ]

I've given some thought to this recently, and have arrived at the conclusion that the only thing I'll ever use to clean up a leak from a battery in the future is a good wipe-down with a dry cloth and/or a brush. Further research on my part has led me to the conclusion that mixing acids and bases (also known as alkalines) typically results in undesirable reactions. Diluting an alkali with a less alkali solution might be appropriate in extreme cases, but I think a good scrub with a brush and a good wiping ought to suffice. We are talking about very small amounts of alkali leaking here, and while these small amounts appear to do a lot of damage, they are chemicals, not living things, and as such cannot go on "Eating" without a sufficient supply with which to do so. Introducing an acid after the alkali has done its job would be rather like closing the barn doors after the bull got out; except in this case, you've now introduced a new potential source of further corrosion that you need to deal with, with potential for a reaction to anything left that may have become less alkali enough to stop eating.

[DigitalQ]

jiminy wrote:
Looks like y'all are right. The blue stuff is in almost all the pins on the near side of Paula and in several pins on Denise. I'll look through the threads on cleaning... I don't have a toothbrush that small! I wonder if people eventually losing their Amigas even after cleaning is not so much due to the cancer being unstoppable as just not being able to get to it all.

Again, to clarify, we're not dealing with a "Cancer" here, but rather a chemical leak. It cannot go on "Eating" indefinitely without something to replenish the supply; once an alkali has "Eaten" something, it becomes neutral. It cannot "Multiply" itself like a cancer.

I tend to believe that people who have lost their Amigas after "Cleaning" them did so by introducing a new chemical to the mix to help further accelerate the damage. Both alkali's and acid's are corrosive, and mixing them together can cause undesirable reactions.

[jiminy]

I see... the holistic approach to healing :-P
So, if you are right, then if I remove the battery, the blue stuff will not spread anymore? I am out of my league scientifically here, but the chemical leaks from the battery to... where? Through the air? It comes down like snow, and sticks to metal but not pcb? Or maybe it does, but the blue stuff is a reaction with metal, while the reaction with pcb leaves no trace. Or does it follow the circuit from the battery through the components, only producing the blue stuff when it hits air? Just thinking out loud here. Probably time for me to go to bed.

[DigitalQ]

jiminy wrote:
I see... the holistic approach to healing :-P
So, if you are right, then if I remove the battery, the blue stuff will not spread anymore? I am out of my league scientifically here, but the chemical leaks from the battery to... where? Through the air? It comes down like snow, and sticks to metal but not pcb? Or maybe it does, but the blue stuff is a reaction with metal, while the reaction with pcb leaves no trace. Or does it follow the circuit from the battery through the components, only producing the blue stuff when it hits air? Just thinking out loud here. Probably time for me to go to bed.

The blue stuff is a result (product, if you like), of the chemical in the battery reacting with the components on the motherboard (the aluminum and PCB material). It has leaked out of the battery and ran along the surface of the PCB to the components. It has taken on a green/blue hue because it has picked up the colour from the PCB; otherwise, when it reacts directly with aluminum, it would be white. The only way more metal and PCB can be transformed into "Blue Stuff" is if more chemical from the battery leaks. When you eliminate the battery, you eliminate the cause of the "Blue stuff."

Once the chemical has reacted and formed this "Blue stuff," it is done. It cannot change itself back into an alkali and continue to "Eat," nor is this "Blue Stuff" capable of eating anything, as it is simply the result of a reaction that has taken place. The reason why you will want to remove this blue stuff is because it shows you where the battery has leaked to, and it is likely that the battery has continued to leak to that spot prior to its removal. I'd remove the battery first, brush off the blue crap next, then use a dry cloth or Q-tip to scrub and pick up any possibly remaining battery chemical.

Any oxidization left on the "Legs" of the components shouldn't hurt, due to the fact that aluminum has an interesting property where, exposed to air, it always constantly oxidizes a self-limiting film which effectively protects it from further oxidization. As such, the concern about air getting to the aluminum traces causing further erosion is unwarranted, and oxidization on the components as a result from the reaction would provide that protective barrier.

[DigitalQ]

Further research on my part has further demonstrated to me that we will want to keep things dry. There is a science experiment where, if you put a small piece of lye on a sheet of aluminum then add water, there will be a reaction between the lye and aluminum. Without water, no reaction can take place. As such, I think this further illustrates the importance of keeping things dry when cleaning up, to prevent further reaction.

[Tenacious]

DigitalQ seems to have put a lot of thought into this.

If, after following the safest and most conservative route, you still suspect an intermittant or high-resistance connection in a chip socket or connector, I have one last ditch thing (if all else fails!) you can try.

AutoZone carries a conductive gel they call "Bulb Grease" for a buck. It is designed for headlight and other exposed connections that tend to corrode. It forms a "liquid" connection and prevents oxidation. I have successfully used this where the pins of a chip go into the socket. The trick is to apply it to the bottom of the pins only and NOT to the body of the chip or any insulator designed to seperate pins. You don't want to create an electrical "short" between pins! After carefull treatment, re-insert the chip.

This will take much care to do well and should probably only be done after everything else recommended here, like just before you give up and throw the machine away.

BTW, if everything does fail, don't pitch the A3000. You or someone can use the good parts in another Amiga. Grin

Good Luck!

[amiga_3k]

For corrosion to work a few requirements NEED to be met, one of them is supply of oxygen, normally fed by open air. In a rather simple black and white world this means that the corrosion should stop once the air-supply is blocked. Blocking it can be done by applying several thin layers of varnish, best the kinds that tends to kreep into narror spaces. One thick layer is not sufficient!

It should be no surprise that the varnish should not enter chip-sockets.

[jagoche]

@amiga_3k

Is there any particular type/brand of varnish that you use?