Ed Cosper wrote:
>
> Hi all,
>
> I need some serious help here. I am experiencing what I believe to be a galvanic reaction
>
>
> Ed Cosper
>
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Hi Ed!
I have come across this problem a couple of times. Some people seems
to believe that certain patterns on a PCB will result in this defect
due to a galvanic reaction. I however believe that this problem lies in
the activation step prior to nickel.It is enough if a single palladium
atom is attached on a trace, then everything in contact with this trace
will be nickel plated. If no palladium is attached, yes, then nothing
in the closed circuit will be plated.The reason why the activation step
fails can have it`s reasons. One is if soldermask residues is present.
And another is that the immersion time is to short. I might be wrong
stating this, it`s just a theory.
Regards
Peter Fogelqvist
Ericsson Circuits

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