[net.micro.apple] Cleaning hardware

binder@dosadi.DEC (The Stainless Steel Rat) (09/27/84)

> Subject: Re: How do clean motherboards?

> IF IT AIN'T BROKE, DON'T FIX IT!  Think about it:  If a machine or board
> is working properly, nothing you do to it is likely to improve the
> situation.  So don't risk immersion in solvents or physical manipulation
> to clean contacts.  Even gentle manpulation can break component leads,
> and many solvents leave behind worse deposits than they remove.

> However, dust and various airborn grime definitely can be deleterious to
> boards.  First, dirt can attract or retain moisture, leading to
> corrosion as well as current leakage paths.  Second, and more important,
> accumulated dust can significantly reduce air circulation around and
> beneath chips, thereby reducing cooling, thereby increasing operating
> temperature, thereby increasing the liklihood of component failure.

Oh, how true!  My machine's keyboard began, over a period of time, to become
flaky - it'd transmit F when I pressed S, S for F, 4 for 2, 2 for 4, and so
on.  The failures occurred more frequently when the weather was warm and
humid.  I figured the encoder chip was bad and replaced it, with TEMPORARY
success.  The new part began to do the same thing.  I checked the power and
everything else I could think of, and finally in desperation applied a solvent
cleaner after blowing at the thing for a while with my lungs.  The keyboard
STOPPED working altogether.  I could see that it was covered with soaked-down
dust kittens and other gunk, and so my last great act of defiance was to take
a toothbrush to it, dislodging all that yecch, and lo and behold, I have a
working keyboard again, with a spare encoder chip for use when the one in use
DOES finally die.  I don't recommend this course of action, but it is clear
that a) solvents can do more harm than good, and b) dust, etc., can cause
serious problems to an ordinary PC board. 

Cheers,
Dick Binder   (The Stainless Steel Rat)

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Posted Thursday 27th September 1984, 08:44 EDT by DOSADI::BINDER