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
>
>
>
>
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