Right you are, sir. I looked it up.
At 20 degrees C and assuming material purity, the resistivity of each are:
Copper: 1.72 x 10^-8
Aluminum: 2.82 x 10^-8
in Ohms per Meter.
In other words, not a difference you could taste.
Jeff/KD4RBG
On Wednesday 12 September 2007 16:01, you wrote:
> Aluminum will work just fine. There will not be enough difference in
> conductivity to matter. Just use a copper to aluminum past when mounting
> any copper conductors.
>
> 73
> Gary K4FMX
>
> > -----Original Message-----
> > From: towertalk-bounces@contesting.com [mailto:towertalk-
> > bounces@contesting.com] On Behalf Of Jeff Carter
> > Sent: Wednesday, September 12, 2007 2:46 PM
> > To: towertalk@contesting.com
> > Subject: Re: [TowerTalk] Copper grounding bus bar
> >
> > I've always wondered about that, skin effect being what it is and all.
> > Why
> > wouldn't aluminum be just as good in this particular application?
> > Considering cost, why wouldn't it be vastly better?
> >
> > I've never met anybody who was worried about the propagation velocity of
> > their
> > ground system. Then again, I don't know everybody, either...yet.
> >
> > Jeff/KD4RBG
> >
> > On Wednesday 12 September 2007 15:38, Jim Lux wrote:
> > > Terry wrote:
> > > > I'm looking at copper sheet on these sites to be used as a SPG plate
> > > > about 16" x 16". What would be the minimum thickness to be
> > > > "self-supporting" as opposed to laminating it on some substrate as
> > > > Polyphaser does?
> > > >
> > > > 73 de Terry KK6T
> > >
> > > unless you want to solder directly to the plate, why not use aluminum.
> > > It's a lot cheaper, much easier to work with (drilling thick copper is
> > > a chore, tapping even more so, prepare to buy many spare taps and use
> > > lots of lube.. soldering to a big sheet of thick copper would require a
> > > fairly high output torch, too). I'd find it hard to believe that the
> > > conductivity difference would be significant (for DC & line frequency,
> > > the thickness of the aluminum helps, for RF, it's a big flat surface
> > > either way). A wide variety of lugs are available, and a nice tapped
> > > hole in the aluminum will make fairly good contact.
> > >
> > > If you feel that the copper is important, slap a big piece of
> > > copperclad PC board material on top of the aluminum, or stick copper
> > > flashing on. You could also put copper foil tape on the aluminum in
> > > places where you think it's important. 3M makes a kind with conductive
> > > adhesive.
> > >
> > >
> > > _______________________________________________
> > >
> > >
> > >
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> >
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