If You Own An A600 Beware

[Loedown]

Hi All,
I am today repairing two A600 units and they have the worst capacitor corrosion I have ever seen on any Amiga boards. If you own one of these units and you haven't had the capacitors changed then I suggest you do it as an absolute priority.

[FOL]

Originally Posted by Loedown

Hi All,
I am today repairing two A600 units and they have the worst capacitor corrosion I have ever seen on any Amiga boards. If you own one of these units and you haven't had the capacitors changed then I suggest you do it as an absolute priority.

Only ever seen bad currosion that takes out mouse tracks and startup ic.

Any chance of some pics?

[Damion]

I have a few trashed 600 boards I didn't even bother repairing. The worst I had ever seen by far, pads and traces disintegrated. This was about 3 years ago already, it can only be worse now. Takes a lot more effort to bring them back once they've reached that state.

It's worth checking expansion cards too, I've had a few Zorro Delfinas, an Ariadne 2, and (most recently) a 4091 with leaky caps.

[Jonathan Drain]

Just checked my spare A600 motherboard, and no leaky caps yet. But it has been switched off and kept in a drawer for at least eight years.

[demolition]

Originally Posted by Jonathan Drain

Just checked my spare A600 motherboard, and no leaky caps yet. But it has been switched off and kept in a drawer for at least eight years.

Keeping it off for very long accelerates the disintegration of the caps as they will start to corrode internally. For this reason they should be charged (Amiga turned on) about once a year.

[lesta_smsc]

You're getting me worried - I have an A600HD in storage!

[FOL]

Originally Posted by demolition

Keeping it off for very long accelerates the disintegration of the caps as they will start to corrode internally. For this reason they should be charged (Amiga turned on) about once a year.

Theres been no conclusive proof of this.
They even studied it and could not conclude either way.

[demolition]

Originally Posted by FOL

Theres been no conclusive proof of this.
They even studied it and could not conclude either way.

ELNA writes that it can increase the leakage current:
http://www.elna.co.jp/en/capacitor/a...on/detail.html
Quote:

When the aluminum electrolytic capacitor is stored for an extended period of time, the leakage current will tend to increase. In particular, this tendency is more noticeable when the storage temperature is high. Please note that applying a voltage can reduce the leakage current. If the capacitor is stored for an extended period of time (more than about two years after manufacturing), condition the capacitor by applying a voltage.

[FOL]

Originally Posted by demolition

ELNA writes that it can increase the leakage current:
http://www.elna.co.jp/en/capacitor/a...on/detail.html
Quote:

Hence the study, how do you explain new old stock machines that were stored since 94, which work perfect and have no leaking caps.

According to that text, it says high temprtures. Dont think we will all be storing our machines in ovens. It also doesnt mention corrosion or leaking. Its talking about the electrical function of the caps.

[demolition]

Originally Posted by FOL

Hence the study, how do you explain new old stock machines that were stored since 94, which work perfect and have no leaking caps.
According to that text, it says high temprtures. Dont think we will all be storing our machines in ovens. It also doesnt mention corrosion or leaking. Its talking about the electrical function of the caps.

If the leakage current increases, it must be due to some degradation of the insulator material of the cap. I wouldn't expect that to cause it to leak, but when it is turned on and operated after a long period of storage, the increased leakage current could cause more heat being dissipated in the cap, which in turn would cause it to leak after a while, so better to replace them before that happens.

Can you provide some details as to this study? It would be interesting to know.

[FOL]

Originally Posted by demolition

If the leakage current increases, it must be due to some degradation of the insulator material of the cap. I wouldn't expect that to cause it to leak, but when it is turned on and operated after a long period of storage, the increased leakage current could cause more heat being dissipated in the cap, which in turn would cause it to leak after a while, so better to replace them before that happens.

Can you provide some details as to this study? It would be interesting to know.

I found a few studies a few years ago, which all concluded the same.
Search around on the net, Im sure you will find them.

I think the main point is. If there is nothing wrong with your machines, then dont mess with them.
I have seen to many people get worried about caps and end up destroying their perfectly good working machines.

I think we are talking about two different things here. OP was talking about leakage, but your talking about electrolyte evaporation.

[roy bates]

i always thought it was a good idea to power cycle these every few months if there in storage.

as fol says i wouldent mess with the caps if there wasent anything wrong, but on the other hand there not getting any younger and its not a bad idea to get someone to do it just to be on the safe side.
although i must say dont try it yourself unless you really know what your doing,it wont take much to destroy a motherboard in the wrong hands.