Hi Jim,
I really doubt the extra resistance makes much difference. A lot of hams
use steel tower sections for verticals...they work well. Check out this
link:
http://www.qsl.net/k9ns/outk9ns4.html
Both the 80 and 160M 4 squares use Rohn 25. Plus, with aluminum tubing you
are looking at having several aluminum-aluminum joints vs. only one with a
steel top rail. I'd be willing to bet that the actual resistance over a 32
foot long piece of either is probably not a measurable difference.
I think the last time I looked the 21' top rails at HD were something like
$12 each.
73,
Gary
++++++++++++++++++++++++++++++++++++++++++++++++
K9GS
Gary Schwartz email: k9gs@arrl.net
Check out K9NS on the web http://www.qsl.net/k9ns/
Society of Midwest Contesters (SMC) GMDXA
++++++++++++++++++++++++++++++++++++++++++++++++
----- Original Message -----
From: "Jim Lux" <jimlux@earthlink.net>
To: <towertalk@contesting.com>
Sent: Friday, November 07, 2003 11:59 PM
Subject: Re: [TowerTalk] 40 Meter Vertical Construction
> Perhaps because it's steel, which isn't as good a conductor as aluminum
> ----- Original Message -----
> From: "Gary K9GS" <GaryK9GS@wi.rr.com>
> To: "Macie, Gordon" <GMacie@innotrac.com>; <towertalk@contesting.com>
> Sent: Friday, November 07, 2003 9:28 PM
> Subject: Re: [TowerTalk] 40 Meter Vertical Construction
>
>
> > Hello Gordon,
> >
> > Why not use chain link fence top rail instead? It comes in several
> > different sizes, is cheap, galvanized, comes in 21' lengths (1 1/2
pieces
> > do the job) and they are swaged on one end.
> >
> > Check them out at Home Depot. If you think you need something different
> > than what they carry look in the yellow pages for a chain link fence
> dealer.
> >
> > 73,
> > Gary
> >
> > ++++++++++++++++++++++++++++++++++++++++++++++++
> > K9GS
> > Gary Schwartz email: k9gs@arrl.net
> > Check out K9NS on the web http://www.qsl.net/k9ns/
> > Society of Midwest Contesters (SMC) GMDXA
> > ++++++++++++++++++++++++++++++++++++++++++++++++
> >
> >
> > ----- Original Message -----
> > From: "Macie, Gordon" <GMacie@innotrac.com>
> > To: <towertalk@contesting.com>
> > Sent: Friday, November 07, 2003 04:17 PM
> > Subject: [TowerTalk] 40 Meter Vertical Construction
> >
> >
> > > I am building a 40 meter 4-square. I have decided to build it with
> > aluminum
> > > from Texas Towers. The bottom section will be 1.625 and reduce 1/8 per
> > > section above that with the top peice being .875. How much do I need
to
> > > overlap or telescope into each section for mechanical strength ??.. I
am
> > > thinking 6 to 12 inches.
> > >
> > > Blurb below from Texas Towers web site.
> > > 6063-T832 Drawn Aluminum Tubing
> > > Typical yield strength of 40,000 psi. The chart shows all available
> > > telescoping sizes which are specifically designed to fit together
> > precisely,
> > > making antenna construction easy, while offering professional results.
> > >
> > >
> > > Gordon N4LR
> > > n4lr@arrl.net
> > >
> > > _______________________________________________
> > >
> > > See: http://www.mscomputer.com for "Self Supporting Towers",
"Wireless
> > Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
> any
> > questions and ask for Sherman, W2FLA.
> > >
> > > _______________________________________________
> > > TowerTalk mailing list
> > > TowerTalk@contesting.com
> > > http://lists.contesting.com/mailman/listinfo/towertalk
> >
> >
> > _______________________________________________
> >
> > See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
> Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
any
> questions and ask for Sherman, W2FLA.
> >
> > _______________________________________________
> > TowerTalk mailing list
> > TowerTalk@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
>
> _______________________________________________
>
> See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
any questions and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk