Question about Dell M991 19" CRT Monitor

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(Dell M991 CRT) Menu repeatedly appears, buttons act erractic

This monitor has been my project for the past few days. Everything else about it is working beautifully. First thing I did was replace the lm7805 regulator which feeds the menu-button board. This appears to have fixed the problem for about 24 hours or so... now its come back with a vengeance. pfft... at least I suppose I'm on the right track. Would a failed storage/decoupling cap have this kind of effect? (at this point I'm thinking theres a loss of stability in the 7805) Maybe adding a heat sink to the regulator (dell didnt place one on it)? Only other possibility I can think of would be altering the resister values along the circuit run from the 7805 to the the buttons then the micro controller (its actually a straight shot, from what I can tell) I'd appreciate any advice, Thanks in advance

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Try removing the control panel, and then removing the plastic caps for the buttons. Clean each button cap and it's corresponding hole in the chassis with rubbing alcohol and an old toothbrush. Often, it's just grime, dirt, coffee or orange juice that causes menu buttons to stick.

Posted on Sep 17, 2008


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Posted on Jan 02, 2017


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