[TowerTalk] SPG Panels/feedthroughs etc

[jimlux]

charlie at thegallos.com wrote:
> We all know that the classic ground panel is a plate of copper of some
> thickness, and also that other than silver, Cu is the best conductor out
> there
> 
> My question - I am thinking of making a ground panel/passthrough
> (combined), and I was wondering how well Aluminum would work.
> 
> Yes, I realize it is NOT as good a conductor (duh), but is it "good
> enough".  I have access to enough 6061 sheet/plate to make what I need, so
> the real question is "when is good enough, good enough"
> 


Aluminum is fine. Steel is probably fine. Physical configuration is 
probably more important than bulk conductivity (it's going to be 
reasonably thick and wide in any case, so it's microohms of 
impedance)... The real issues are mechanical connection (how do you 
avoid oxide films forming, etc.) and things like thermal expansion 
mismatch leading to gradual loosening. Getting a good electrical bond to 
aluminum that will last is non-trivial.