Obviously sounds heat related. Look for barrel cracks in the vias.
Often, barrel cracks don't get detected during normal electrical testing
done at room temp but show up when heated.

Paul Terranova
Digital's Analytical and Environmental Test Services Lab
508-467-3109
[log in to unmask]

        ----------
        From:   Christy Graham[SMTP:[log in to unmask]]
        Sent:   Wednesday, March 11, 1998 2:19 PM
        To:     [log in to unmask]
        Subject:        [TN] ASSY: Intermittent Short

        TechNet,

        I was told recently of a printed circuit card assembly that,
when the
        assembly is powered up in the morning, the board runs, but that
by the
        afternoon, it fails.  Next day, same board, same results.  The
engineer
        thinks this problem is due to a "flux short".  Is this possible?

        Christy Graham
        [log in to unmask]

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