The invention relates to a method comprising supplying a test signal to a first pad part of the pad; measuring the occurrence of the test signal through a second pad part of the pad or a part of the printed circuit board connected to the second pad part, which second pad part is separate from the first...http://www.google.com.hk/patents/US6552558?utm_source=gb-gplus-share專利 US6552558 - Testing fastenings of printed circuit board
