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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: ciVic on August 21, 2015, 11:32:58 PM
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Hi all,
some years ago I've noticed some gfx issues with my A600. Last week I found out that two traces on the board were broken. Additionally the pins of the IDE connector break like they were never fixed to the plastic part of the pin header. I found some blue/green chemicals between the IDE connector and the pin header so I assume that acid from the caps etched my traces and the pins.
So here is my theory. Now the caps are dry. That's why there were no new damages in the last years. But if I would recap the board, it would again cover my board with acid resulting in more damages. So as long as the caps are more or less working (e.g. sound is silent but working) we should not recap. What do you think?
Additionally we should clean our board regularly with some KONTAKT spray or something similar, maybe on an annual basis.
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No, you should recap that board. But first you need to clean it up by neutralizing all the acid, repairing any damaged traces and then recapping it.
Those smd caps on A1200s and A600s are ticking time bombs.
Don't be lazy, repair that board.
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I think you should.If you don't then component behind bad cap will try
to pull electric power it was designed to operate with and in that process
something will get hot and in the end burn out.Caps are cheap to get while
Amiga custom chips are hard to find.It takes long time for cap to dry/leak
on average Amiga and if you worry about that you can always replace cap
with better one that will last longer (for example 1000 microF 10 V cap can
be replaced by 1000 microF 16 V cap that will get less hot and last longer.
You don't have to replace all caps , there is a small piece of kit to test capacity but you still need to take it out of motherboard to do that.
I would advise 60-90 % ethanol alcohol to clean motherboard , anything that
can eat away at contacts would be disaster.Also , PSU should be kept in
good shape too.It can cause damage to caps.
And SMD (ceramic looking) caps can be replaced with regular ones if you are handy enough.
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Depending on where you are there are a few places around the globe that can do this AND clean the board professionally.
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only you want to keep using them;)
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No, you should recap that board. But first you need to clean it up by neutralizing all the acid, repairing any damaged traces and then recapping it.
Those smd caps on A1200s and A600s are ticking time bombs.
Don't be lazy, repair that board.
The standard (cheap) SMD Electrolytic capacitor of the 1990's contained "Borax" not Boric Acid; when the Borax combined with moisture in the air, it forms an alkaline liquid that dissolves the copper traces. Use of more alkali to neutralize a this will result in further damage.
REF: http://www.intralabs.co.uk/borax.html
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I think you should.If you don't then component behind bad cap will try
to pull electric power it was designed to operate with and in that process
something will get hot and in the end burn out.Caps are cheap to get while
Amiga custom chips are hard to find.It takes long time for cap to dry/leak
on average Amiga and if you worry about that you can always replace cap
with better one that will last longer (for example 1000 microF 10 V cap can
be replaced by 1000 microF 16 V cap that will get less hot and last longer.
You don't have to replace all caps , there is a small piece of kit to test capacity but you still need to take it out of motherboard to do that.
I would advise 60-90 % ethanol alcohol to clean motherboard , anything that
can eat away at contacts would be disaster.Also , PSU should be kept in
good shape too.It can cause damage to caps.
And SMD (ceramic looking) caps can be replaced with regular ones if you are handy enough.
i agree clean the leakage up.
replace ALL the caps, not some, they are all past their service life by many years and for the price it makes sense.
dont use low percentage alky ,it means it has water in it. 90% or better isopropyl is best. 100% being ideal.
are you suggesting replacing electrolytics with cermaics? this is not a good idea especially if in the power circuit.
as Dan said above, cap leakage is alkaline(much like amiga clock batts..Nuetralize it with a acid first,such as vinegar,then clean it all off properly.
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The other way around - replacing SMD ones that Dan mentioned with
regular through-the-hole ones by bending their legs at 90 degree angle.
They are unlikely to leak.
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Now the caps are dry.
They'll stop functioning at some point, dry or not.
But if I would recap the board, it would again cover my board with acid resulting in more damages.
Only if you wait until the new ones start leaking :rolleyes: Won't happen for years if you have good ones.
Look, capacitors are an essential part of electronics. They have to be in good working condition. Replace them with capacitors from a good brand, and always replace them before they start leaking (seems so obvious).