[sdiy] Grounding of inputs/outputs for modules

[David G Dixon]

> I seem to recall you're a materials type, so pardon the 
> question, but doesnt aluminum oxidize?  Can a mechanical 
> panel to socket connection be trusted electrically long term? 
>   These are dis-similar materials as well, no?

Aluminum oxidizes instantly when exposed to air to form an invisible
nanolayer of aluminum oxide, Al2O3.  This oxide layer passivates the
aluminum perfectly.  As long as this layer isn't exposed to acid, the
underlying aluminum will never corrode.  That is the secret to its
widespread use, even in highly oxidizing environments.

As far as I know, none of the panel-to-jack connections has ever failed in
my modular.  If it were a problem, I could easily wire up all the jack
rings, but it simply doesn't seem to be necessary.