Keithley 129 Display Repair

The LCD on my Keithley 129 multimeter (which was the first big investment into my electronics hobby ~1982) has turned black over the years. The original LCD is a custom type with zebra-rubber contacts on one side, for which I could not find a source:

The original display (with top polarizer removed)

The standard 3.5 digit displays are too big to fit – however, Digikey has one slightly smaller display that fits: the VI-301 from Varitronix. To mount this, I 3D printed an adapter plate:

Wiring it up:

Keithley 129 wiring

A bit smaller than the original, but working fine:

Keithley 129 after repair

2016-12-27 by rincewind