Method and apparatus for testing circuit boards

Abstract

The disclosure shows the use of a plurality of individually moveable probes in an X-Y plane which may contact points of networks on a circuit board on either side thereof and measure the discharge time of a charged network. The specification also discloses the utilization of a common connector to a conductive reference plane to provide a terminal point for any of the plurality of probes. Each probe is a dual-purpose probe in that it may be utilized for a discharge test of each network, or it may be used in a combination with another probe to measure the resistance of a network. In most instances, the circuit board under test will include a common conductive reference plane which may be utilized as one side of a test source. Each network is tested as to discharge time against a norm which is previously determined; if the discharge time is too long above the norm, such long discharge time will indicate a possible fault. If the discharge time is too short the short discharge time will indicate a possible fault in the network. The probes may be switched from the discharge circuits to a mode in which two probes are connected to a power source and resistance measuring circuit to measure the resistance of a network or parts thereof to check for continuity or to measure the resistance between two networks to check for a short between two networks.