HP-42S work-around for sticking to low contrast LCD problem


Hi all.
(It might be good news for DavidShenk.)

I recently bought an HP-42S which has LCD contrast problem that seems to be identical to the case of the previous thread
'An HP-42S fix success, and a contrast problem'.

I tried another way to generate the LCD bias voltage, and the work-around seems to work well so far.

for more information -
A work-around for sticking-to-low-contrast LCD problem of the HP-42S



Edit: URL to the image corrected.

Edited: 1 Feb 2010, 5:03 p.m. after one or more responses were posted



What I bought (at Yahoo JAPAN auction) and repaired is identical to DavidShenk's.


This is a version A with the flush display, S/N 2942S30206 and it passes it's self test.

It's a small world.


I take a few days off checking the forum and when I come back you've got my calculator! I did not realize you were the buyer. I had reached a dead end and just couldn't do anything else with it.

I'm glad you were able to find a fix. You always do a good job documenting what you do, and I think it will be a good help to others in the future.

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