I've been playing with verticals, mostly for 160/80/40, for almost 50 years.
The one constant in all that time is the widely varying opinions.
Jim said:"" Recently published work by N6LF, and much older work in the ARRL
Antenna
Book differ strongly with that statement ""(the statement being about
resonant radials)
There are just as many, if not more, that support my statement. I've
actually gotten my hands dirty testing both types of systems. I've found, in
real world tests, that totally resonant systems perform better than
non-resonant. I don't believe in, or even use, computer modeling like NEC,
etc. I've built vertical antenna systems as a W9 in Illinois, a W6 in
California, and several systems the last 15 years here as a W7 in Arizona.
The totally resonant systems, from my observations, have a slightly wider
bandwidth and from all indications a slightly lower angle of radiation. I
only use the verticals for DXing with stations outside North America. I have
wire antennas for working the high angle propagation for working North
American stations.
All that being said right now, on 80m, I'm using a non-resonant system. I'm
not using radial wires, basically I'm using a rectangular screen. There's
less bandwidth but much better performance especially to Europe on 75m SSB.
73
MAL
N7MAL
BULLHEAD CITY, AZ
http://www.n7mal.com
Everyone in the world is
entitled to be burdened
by my opinion
----- Original Message -----
From: Jim Brown
To: towertalk@contesting.com
Sent: Tuesday, December 22, 2009 5:10
Subject: Re: [TowerTalk] Hy Tower
On Mon, 21 Dec 2009 23:38:03 -0000, N7mal wrote:
>In other
>words if you're going to operate on 160m then the radials need to be at
>least 127ft. If your lowest freq is 80m then your radials need to be a
>minimum of 67ft.
Recently published work by N6LF, and much older work in the ARRL Antenna
Book differ strongly with that statement. In general, it is a waste of
wire to make radials much longer than the radiator itself, and according
to N6LF's recent work, it can even HURT performance to make them much
longer.
>You don't really need any more ground rods but you do need
>more radials. It has been my experience you can never get enough radials
>under a hy-tower, but you should try to get at least 50.
Strong agreement on that. Ground rods are for lighting protection. They
have nothing to do with how well an antenna works. And MORE radials is
definitely a good thing.
73,
Jim K9YC
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