KM1H wrote:
> Dont knock it if you havent tried it.
> I for one am convinced that elevated radials are the only way to go when
> the ground beneath them has the conductivity of granite.
Perhaps. But, my reponse was to someone was talking about "burying" 3000'
of radials. That didn't leave me with the impression he was talking about a
vertical over the rock piles that you speak of, but rather over ground with
average conductivity.
73,
Tom, NI1N
----- Original Message -----
From: "jeremy-ca" <km1h@jeremy.mv.com>
To: "Tom McAlee" <tom@klient.com>; <TowerTalk@contesting.com>
Sent: Friday, June 08, 2007 8:23 PM
Subject: Re: [TowerTalk] elevated radials vertical
>
>>
>> In any case, I kind of like that people think their elevated systems work
>> just as well. It makes for less competition in the pileups.
>>
>> 73,
>> Tom, NI1N
>
>
> Dont knock it if you havent tried it.
>
> At my prior QTH I used a 100' tower with a Christmas tree of W2PV
> monobanders as a shunt fed vertical on 160. I started with 4 radials 2"
> under the sod and couldnt even crack a pileup. By doubling the number and
> spending a week or so testing and then doubling again and again until I
> reached 64 I was convinced I was wasting my time. I was surrounded on 2
> sides by swamp and the ground was always moist back by the tower and most
> of the radials.I had fair results but nothing to get excited about. I
> "felt" about 10dB below the top guns.
>
> On a whim thru an ad in the Want Advertiser I bought 4, used one year,
> rolls of 4' x 50' galvanized fencing that was plastic coated. It had a 2"
> x 4" mesh and all crossings were welded. When I put those sections down at
> the base of the tower I worked everything I could hear and that was with a
> measly 1200W; QRP by the standards of many on 160. This was years before
> computer programs and articles praising a heavy concentration of radials
> right at the base of the antenna had just appeared. There wasnt even a DX
> Cluster back then, it required actual skill to find and work a new one.
>
> Moving to this QTH which is a hilltop rock pile I had no desire to waste
> my time on ground radials. Starting with one sloping vertical hanging from
> a 160' guy level wire I started the same radial process, elevated 10' .
> With some lab equipment this time I recorded the feed impedence starting
> with no radials and just a slant driven ground rod in the topsoil. With 20
> 135' radials I reached the point of no further improvement altho I went to
> 40 to be sure. The feed line was decoupled with about 12" of large ferrite
> beads.
>
> The next step was a second vertical using those left over 20 radials and
> then the phasing and direction switching for broadside and endfire. As
> many can attest that array was always at the top of pileups for the
> several years it was active. I also had an inverted V at 160' for
> comparison and high angle openings.
>
> Having lost interest in ham radio about 8 years ago I went back to my
> other passion, building hot rods. Now retired I have time for both
> obsessions and the array maintenence is in process. I just might add 2
> more verticals and then duplicate it on the 100' tower for 80M.
>
> I for one am convinced that elevated radials are the only way to go when
> the ground beneath them has the conductivity of granite. AM broadcasters
> learned a long time ago that high rock piles were no place for their
> antennas and buried radials.
>
> Carl
> KM1H
>
>
>
>
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