[Antennas] Re: [TowerTalk] Metal House Siding and Antennas

[Mark Nelson]

 Well, as an aside .. or perhaps "head-on" .. .. .. an important source for
info on this subject can come from hams that live in mobile homes, and
mobile home parks.  Been there, done that (didn't get no stinkin' tee shirts
those days) ,, A low array (read, SHORT TOWER) for HF can get really screwed
up by this situation, not to mention the problems encountered by LB are
"enjoyed" throughout the neighborhood in a mobile home park!
Obviously, the lower the frequency, the more the radiation pattern(s) are
"skewed" -- and it tends to show up far more on transmit than receive,
unlike the legendary isotropic source.  A tri-band yagi at 35 feet will be
really affected on 20 meters ... while at 70' -- well, it will be, but to a
much lesser extent.   A metal roof also can also cause anomolies in antenna
radiation patterns, sometimes an unexpected plus!  If you have a 150' tower
.. don't think you will see a perceptible difference.   If you have a 30'
tall metal structure, with an ajoining  50' tower ... expect something
different than you will see on your YO program! 73 .. Mark, AA6DX

-----Original Message-----
From: L. B. Cebik <cebik@utkux.utcc.utk.edu>
To: Nelson P. Moyer, Ph.D. <nmoyer@uhl.uiowa.edu>
Cc: antennas@qth.net <antennas@qth.net>; towertalk@contesting.com
<towertalk@contesting.com>; dx@ve7tcp.ampr.org <dx@ve7tcp.ampr.org>
Date: Tuesday, September 09, 1997 5:03 PM
Subject: [Antennas] Re: [TowerTalk] Metal House Siding and Antennas



>I lived in a house many years ago with aluminum siding and encountered the
>following problem (as closely as I can analyze it:  junctions of siding
>strips to another created what as best I can tell amounted to diode
>junctions that produced an array of signals (mine) at many frequencies
>above and below the operating frequency--all the way from broadcast AM
>band to TV.  I am certain that the siding strips were not electrically
>bonded.  Whether metal siding has improved since those days, I cannot say,
>because I have never let myself live in or next to an aluminum sided
>house.  I have resided a house in quality vinyl and must say that I like
>the properties of that siding--both as a siding and for amateur radio
>purposes.
>
>These are the experiences of one person, and hence should not be
>generalized too far.
>
>-73-
>
>LB, W4RNL
>
>
>L. B. Cebik, W4RNL         /\  /\     *   /  /    /    (Off)(423) 974-7215
>1434 High Mesa Drive      /  \/  \/\     ----/\---     (Hm) (423) 938-6335
>Knoxville, Tennessee     /\   \   \ \   /  / || /      (FAX)(423) 974-3509
>37938-4443     USA      /  \   \   \ \       ||              cebik@utk.edu
>         URL:  http://funnelweb.utcc.utk.edu/~cebik/radio.html
>
>
>
>
>------
>Submissions: antennas@qth.net
>


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