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Default Cell Phone -- What remains wet?


"Dan Dubosky" wrote in message
...
Thanks to all who have contributed to this thread. I have benefited from
all of the remarks. I must admit I wasn't thinking of residual mineral or
other type of deposits. When dry I thought that these would be in the
order of megohms and since the cell phone works at such a low voltage,
they would not matter.

Everything that I had around, distilled water and alcohol, had measurable
conductivity. I even measured some vodka. It too had measurable
conductivity, but after properly disposing of it, I didn't care as much.
So today I bought some Electronic Cleaner at my local Radio Shack. It
comes with a brush to clean the printed circuit board. By tomorrow I
should know whether I accomplished anything.

Thanks to all again,
Dan


In general, the first rule with any kind of liquid damage, is get the
battery out as fast as possible. I have on many occasions seen the results
of electrolytic action across close spaced tracks and component legs, as a
result of small currents passing through the liquid that is doing the
contaminating. This often leaves a conductive 'corrosion' mess behind it,
that can be quite difficult to remove, and tends to leave component legs and
solder joints, a dull grey. Solder thus affected, is very difficult to
reflow. Thru' plated holes can also be attacked, and if it gets that far,
you are in trouble ... The areas usually worst affected, are those where
the voltages and current availabilities, are highest i.e. around the power
supply, so that may well go along with your apparent battery discharge
problems.

The second most important rule with liquid damage, is to get the item into a
warm dry place as soon as possible, for at least 24 hours, before putting
the battery back in. In the UK, that usually means the airing cupboard,
where the household hot water storage cylinder is located. I've no idea
whether houses in other countries have a similar cupboard, where bed linen
is kept, for instance.

Following these two 'rules', will often result in full recovery of the item,
with no ongoing problems.

Arfa