[mythtv-users] Replacing the Power Button with a Lock and Key

[f-myth-users at media.mit.edu]

    > Date: Thu, 21 Jun 2007 15:52:20 -0400
    > From: joe.white at wachovia.com

    > Not trying to prevent purposeful power-offs.  Just the accidental ones. It 
    > happens once every other month and a key is cheaper than a new case and 
    > easier than rearranging the world.

It may be ugly, but have you considered just making a guard?  I had to
do this once with a Mac Quadra that I kept bumping with my knee; in
that case a simple strip of cardboard taped to the case was enough.

In your case, you might want to find something slightly more concave
on the bottom; maybe the back of the battery compartment for some
unused remote, or a yogurt lid, or whatever, and just tape the top
edge to the case.  (That way you can still flip it up and push the
button.)  It's probably way faster and easier than installing a
keyswitch, and might even look better, since installing a keyswitch
will probably require machining the case in some way depending on what
you've got.

The other solution is either to pull the switches out of the face of
case entirely and put them inside (so you have to open the case to
push them), or to wire a switch or two -in series- with the existing
switches---if you make it some sort of momentary toggle or pushbutton,
you'll have to hold that down -and- push the relevant case button,
which makes it much less likely to be done by accident, especially if
they're in different locations.  This latter might be the easiest
solution, because you can just run the relevant wires out through a
tiny seam or some other hole in the case, tape them onto the back of
the case (or somewhere else out of sight), and then you haven't made
the case any less pretty, while still making it possible to reset the
machine if you want.

[If power & reset share a common ground, you might be able to put a
single switch in series with that ground and only have to add one
switch.  Obviously, test that pushing both power & reset without your
series addition pushed won't nonetheless boot the machine, since there
might be sneak paths; pullups, etc that make this not quite as
straightforward.  The safest solution is to put a different switch
in series with each of power & reset.]