Electronics Forum | Wed Sep 08 17:49:19 EDT 2004 | gregoryyork
Knock off some balls and you may find it has a flat bottom to it were it has mechanically stuck to the solder resist usually seen under 60X magnification. Common with Liquid photoimageable resist (I know again) Best way to check resist cure is to pay
Electronics Forum | Tue Oct 09 21:45:21 EDT 2012 | davef
Hi Bob Ideas to consider are: * Use your handheld XRF * Swab vinegar on the copper and watch it brighten * Use the following procedure Nearly all copper minerals can be dissolved by melting with a mixture 1:2.5 of ammonium chloride and ammonium nit
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