I use 4 elevated radials under each element on my 4 squares for 40m and 80m
with Comtek box and am very happy with the performance of both systems.
W1XT (a near neighbor) prefered 8 elevated radials under his parasitic fed
arrays.
We rated the systems as equal. If he could hear/work the DX, so could I,
and vice versa.
Both of us erected two radials as a dipole and trimmed them for resonance at
our desired operating frequency. Due to the proximity to ground (9' feet)
they come out a little short (physically). Then we installed the rest of
the radials at the same length. After all the radials were installed we
installed the vertical elements and trimmed them to the desired operating
frequency, which due to the slightly short radials made the vertical portion
slightly long. This raised the feed point impedance slightly and tilted the
radiation lobe down a bit. Not enough to measure but by theory.
I don't consider forward gain as my array's strong point but they both have
excellent front to back and front to side. They do have some forward gain
though because I have busted a lot of pileups with them.
de Paul, W8AEF
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of Yo3ctk
Sent: Friday, October 22, 2004 11:50 AM
To: Tom Rauch; towertalk@contesting.com
Subject: Re: [TowerTalk] Ground radials/elevated radials
The same would hold true for elevated radials?
I am designing a 4-square for 80m. Full size verticals. Comteq
phasing/switching unit. But I need elevated radials for practical reasons
(the land below is used for small-size agriculture). I am not sure how many
and how long radials are needed for each antenna. I am not after the
ultimate system, only one with decent results.
Thank you for any suggestion. Best regards,
73 de Mike, YO3CTK (YR7M in contests)
----- Original Message -----
From: "Tom Rauch" <w8ji@contesting.com>
> No. Radials needs to be as many as long and as straight and evenly
> spaced as possible. If they are close to ground or on ground, you need
> 20-30 0.2 wavelength long to have a really good ground. About 50 or 60
> radials is nearly perfect.
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
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_______________________________________________
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.
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