The DZero project at FermiLab required cables with a very fine pitch and tiny connectors.  The IDL built a hand-held unit and set of adapters that could test various cables up to 50 conductors.

There are two general modes.  The first, which needs no accompanying computer, checks continuity on each line and checks that there is no short with nearby conductors.  Success is indicated by LEDs.

In the second mode, the unit has capability of measuring resistances on each line to determine the quality of the connector installation and the resistance between any line and the adjacent lines. A set of solid-state switches driven by CPLD circuits makes the connections necessary for the resistance measurement.

Click on the images to see a larger view.