replacement LCD for 7129 voltmeter chip

[jmelson]

I have a pretty fancy photometer that uses the ubiquitous 7129CPL chip and a fairly big 4-1/2 digit LCD that has apparently gone bad.  Does anybody know where to get replacement LCDs?  It is in a DIP sort-of arrangement, with 40 pins, and is 3.5" x 1.5"

It MIGHT have special range indicators on the right edge, but I guess we could live without those.  The indicators to the right of the digits are uW and nW, and above the digits LOW BAT and A/W.

The digits are probably 0.6" tall.

Thanks for any hints,

Jon

[floobydust]

Look for a part number or any markings on the LCD. Usually on the underbelly.
There's many different manufacturers (and different pinouts) but it is likely a customized part with the units uW nW etc.

[CJay]

https://uk.farnell.com/c/optoelectronics-displays/displays/lcd-displays/7-segment-lcd-displays

[jmelson]

Interesting result.  So, while poking around trying to determine if a pin was no longer connected to the tin oxide LCD electrodes, the display started looking better.  After about an hour of operation, it was basically fully back to normal.
I had not even powered this unit on in ten years.  I'm guessing an electrolytic cap had started getting leaky, and took an hour to reform the dielectric.  Once voltages were back to normal, it worked OK.

Jon