Maker Pro
Maker Pro

Confusing PbF inspection test appearance.



Jan 1, 1970
Anyone else come across this PbF situation?
With pbf solder joints on green finish pcb
and viewing pins for solder problems under x30 microscope.
Perhaps an optical effect from the curvature of the solder blobs
being concave rather than convex. Makes
it appear as though there are green rings around the pins as though failed
solder and you can see the underlying board through a solder ring-crack.
As viewing pin end on it is all a bit iffy.
To convince yourself it is an optical effect , surround the pin ,covering
the green board
with sticky paper labels of another colour and this green ring turns to the
colour of the paper