Pacitive electrode system for detecting open solder joints in printed circuit assemblies

A test probe for testing an electrical component to determine whether a connector lead of said electrical component is conductively connected to a trace of a printed circuit board, said test probe comprising:

• a thin conductive plate for capacitively detecting an electrical field generated by said connector lead of said electrical component whenever said connector lead is conductively connected to said trace producing a test signal, whereby said conductive plate is substantially planar enough such that said conductive plate can be used to test varying shapes and sizes of electrical components;
• a substantially planar thin guard plate disposed in close physical proximity with and substantially parallel to said substantially planar conductive plate for providing shielding from electrical noise;
• signal amplification means electrically coupled to and in close physical proximity with said substantially planar conductive plate for amplifying said test signal to increase the signal to noise ratio of said test signal to said electrical noise, said signal amplification means and said shielding means being disposed in sufficient proximity to said substantially planar conductive plate means to generate a test signal that has a sufficient signal to noise ratio to determine whether said connector lead is conductively connected to said trace;
• and
• a thin dielectric material disposed between said substantially planar thin conductive plate and said substantially planar guard plate, creating a sandwich probe structure comprising said substantially planar thin conductive plate, said thin dielectric material and said substantially planar thin guard plate respectively, said sandwich structure being substantially planar and thin such as to enable a user to cut said sandwich probe structure to a desired size and shape.