An HP-42S fix success, and a contrast problem Message #1 Posted by DavidShenk on 1 Dec 2009, 2:15 a.m.
I bought a "dead" 42s from TAS for $20 USD with shipping, so I was happy with that. After putting batteries in it, I got a constant on and off beeping. I looked that up and most opinions pointed to a bad RAM chip. I've now done a few upgrades on these, so I decided to upgrade this one. After taking it apart, I put the batteries in it one last time and it now wouldn't even beep. I finished the upgrade and it now works! Very happy with that. (Side note: It had a Toshiba RAM chip in it, the only one of those I've seen so far)
Now I notice that I can only see the display if I'm looking at the screen from a very low angle. If you look at it straight on, it literally looks off. No problem I thought, but when I went to adjust the contrast, nothing. The contrast will not change at all, and seems to be stuck in low :(
This is a version A with the flush display, S/N 2942S30206 and it passes it's self test.
Has anyone else run into this, or have any ideas?
Dave
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