Drive device for an apparatus for electrical function testing of wiring matrices

A drive device for electrical function testing of wiring matrices, particularly of printed circuit boards, having a carrier plate located over the wiring matrices the carrier plate having a plurality of gas discharge channels each provided with at least first and second electrodes, whereby at least two selected measuring locations (test points) of a wiring matrix are contactable via the allocated gas channels and their electrodes, respectively, whereby every channel being equipped with at least two electrodes is selectable based on a coincidence principle via a plurality of first and second electrode bus lines allocated to these electrodes, first electrodes of the channels being connected in series via the first electrode bus lines and second electrodes of the channels being connected in series via the second electrode bus lines, comprising a voltage (U.sub.z1) being applied to a first electrode bus line (O.sub.1) and to a second electrode bus line (U.sub.1) for a first selected channel, this voltage (U.sub.z1) being adequate to ignite a gas discharge between the first and second electrode bus lines (O.sub.1, U.sub.1) in the first selected channel;

• and further, a voltage (U.sub.z2) being applied to the first electrode bus line (O.sub.2) and to the second electrode bus line (U.sub.2) for a second selected channel, the voltage (U.sub.z2) being adequate to ignite a gas discharge between the first and second electrode bus lines (O.sub.2, U.sub. 2) in the second selected channel;
• and, for testing for a conductive connection between the first and second channels, a difference (U.sub.p) in potential being applied between the gas discharges, this difference in potential (U.sub.p) effecting a current conduction (I.sub.p) from the gas discharge between the first and second elected bus liens (O.sub.1, U.sub.1) in the first channel to the gas discharge between the first and second electrode bus lines (O.sub.2, U.sub.2) in the second channel via conductive connection between the two selected measuring locations when a conductive connection exists.