Tin whiskers and other packaging problems

[Pat Pending]

Thanks Mark. The sample size was not great. However if you consider that these types of equipment were put into cold/hot temperature gradients and high humidity, basically damp factory's, not peoples living rooms, if this problem could crop up, it did. Incidentally the TO18's weren't tossed out, as the problem with them was on the underside of the package, not internally, they would just be removed, cleaned, dipped in black enamel paint, and resoldered back in place, a Soviet semiconductor manufacturing idea, but it works!  Earlier in my TV and radio repair trade days, a colleague would use this trick on transistors he replaced maintaining "it keeps out the damp", so the idea was not mine to claim. Regards. Andy.