-----Original Message-----
From: Gerry Cooper <[log in to unmask]>
To: [log in to unmask] <[log in to unmask]>
Date: Wednesday, June 14, 2000 1:30 PM
Subject: Re: [TN] Gold over Copper?!?
--------------------------------------
Gerry
Its good to see someone else that also goes back that far on pcb,s. A good
bit of the guiden systems from North American Avaition (later Rockwell) for
the space program were gold boards, for the the early days thats all that we
made.
Frank
------------------------------------------


>Many years ago all circuit boards were plated with 100 U of gold directly
over
>copper.  This changed to 50 u when nickel was added, and later went down to
30
>u.  The problem is that copper migrates up through the gold if it is not
thick
>enough, the nickel acts as a barrier layer.
>
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