A 1.5 volt battery may not be enough to breakdown any contact
'resistance' in the tower joints. I'll bet a KW of RF (or even 100W)
does a lot better :-)
Someone suggested using a CURRENT SOURCE set to 1 AMP
and then measure the Voltage across the antenna joints. Sounds
like a better solution to me.
Tom N4KG
On Tue, 19 Nov 2002 11:05:40 -0800 Steve Katz <stevek@jmr.com> writes:
> Interesting subject.
>
> I'm sure this varies a great deal, but I measured the resistance
> from the
> top to the bottom of 70' of R25 that had been up for a couple of
> years, and
> it was very high. (Measurement made by attaching #12 insulated
> copper wire
> to the top plate of the tower, running that wire to the bottom of
> the tower,
> and measuring the resistance from "top" to "bottom," assuming that
> 70' of
> #12AWG pure copper is zero. It's not zero, but it's damned close.)
> In that
> case, I measured more than 20 Ohms through the tower. Banging hard
> on the
> guy wires could change it very slightly, but not as much as I
> thought it
> would.
>
> I don't think I'd want 20 Ohms in series with my 50 Ohm antenna, but
> that's
> just me!
>
> -WB2WIK/6
>
> "If everything seems under control, you're just not going fast
> enough." -
> Mario Andretti
>
> > -----Original Message-----
> > From: Pete Smith [SMTP:n4zr@contesting.com]
> > Sent: Tuesday, November 19, 2002 8:21 AM
> > To: towertalk@contesting.com
> > Subject: Re: [Towertalk] tower joint Conductivity ???
> >
> > At 10:45 AM 11/19/02 -0500, k7lxc wrote:
> > > > Should I use conductive grease?
> > >
> > > I would. But hard to predict the conductivity of the whole
> tower.
> >
> >
> > I may be living in a fool's paradise, but I figured that with 2
> bolts per
> > leg per joint, plus the zinc-on-zinc contact of the legs on top of
> one
> > another, pressed together by the weight of the tower and guy
> forces, the
> > conductivity between sections ought to be pretty decent.
> >
> >
> > 73, Pete N4ZR
> > Sometimes a tower is just a tower
> >
> >
> >
> >
> > _______________________________________________
> > AN Wireless Self Supporting Towers at discounted prices,
> > See http://www.mscomputer.com
> >
> > Wireless Weather Stations now $349.95. Call Toll Free,
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> > Towertalk@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
> _______________________________________________
> AN Wireless Self Supporting Towers at discounted prices,
> See http://www.mscomputer.com
>
> Wireless Weather Stations now $349.95. Call Toll Free,
> 888-333-9041 for additional information.
> _______________________________________________
> Towertalk mailing list
> Towertalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
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