We have recently run across a situation which has baffled us.  On the PCB
in question there are 4 Wave soldered PLCC sockets. 1 of these is being
reported as having solder shorts underneath.  On the returned units we x-
rayed the sockets ( can't see under) and found shorts on 1 socket location
only.  The shorts were consistanly on the same pin area for all the sockets
were the shorts were found.  We removed a socket only to find the board
very clean underneath...no shorts..
The socket has a bottom retainer to hold all the pins in place.. This was
pried off and to our surprise there was the short.. inside the connector.
The amount of solder was enough to surround 3 pins in 2 seperate areas.
The hole around the pins in the plastic base is no more then 0.002".

Does any one have any idea how solder could have gotten up inside the
connector ( consistantly in the same location)? Or has any one seen this
before?

We have run this assembly several times in the past with no difficulty.

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