Abstract: For detecting whether a probe (P) is in contact with an electrical circuit under test (U), capacitance measurement means (M) measures the capacitance between the probe and a reference (G), without the probe contacting the circuit. The measured capacitance is stored in control circuitry (T) and then a capacitance value is measured between the probe and the reference with the probe in a position in which it is assumed to be in contact with the circuit, the control circuitry comparing the measured value with the stored capacitance.
Abstract: A method of testing for short circuits between networks of a printed circuit board comprising a plurality of such networks comprises measuring an impedance value between each of the networks and a ground plane of the board, using a pair of probes; and, also using the probes, effecting tests for short circuits only between any two networks for which the measured impedance value is substantially the same and for which this measured impedance value is greater than a predicted lowest impedance for the two networks to be short-circuited together.
Abstract: For contacting electrical pads of different geometries, an electrical testing probe including a probe body which is generally laminar and which tapers downwardly to provide a contact portion; and a carrying member which carries said probe body.