2 different LCD problems, 2 repair attempts, 2 times the disappointment

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In this video we take a look at a pair of Casio FX-841P pocket computers sent in from England for repair. They both have LCD troubles, but each is a unique problem. We’ll do our best to get this pair of pokecoms purring perfectly. But sometimes fate has other plans.
Timeline:
00:00 - Welcome
01:31 - Unit #2, missing rows on LCD
09:50 - LCD reseal attempt
13:57 - Testing and bodging
18:18 - Unit #1, dim LCD
21:51 - Testing and sadness
25:34 - Replacing mystery cap, test #2
27:37 - Wrap up
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[@mileselectronicsstudio7316]

I have some pocket computers that also have poor contrast and have tried replacing the big caps with pretty much the same result as you. Maybe the chip caps in the LCD voltage divider circuit might be going bad, have not tried to replace any of them yet. Could also be the LCD driver chip(s) is going bad but unless you have a few of the same or similar model, that is hard to troubleshoot as well. Could also be the LCD display itself, or perhaps one or both of the polarizer films are going bad, I have seen this on CASIO FX-7000G Graphing Calculators where the back polarizer on the LCD will oxidize and create dark spots. Too bad we can't find some old Casio parts or service centers where they still have the LCD displays and the Heat Tapes. Those spare parts would come in very handy 30+ years later! As always, great video and thanks for showing the good with the bad videos. Keep up the awesome work Jeff! Regards, Carl Miles

[@wimwiddershins]

Pretty amazing Jeff. You've got more patience than I.

[@andrewoneill4690]

Cheers Jeff!