> -----Original Message-----
> From: towertalk-bounces@contesting.com [mailto:towertalk-
> bounces@contesting.com] On Behalf Of Rick Karlquist
> Sent: Monday, April 02, 2007 9:28 PM
> To: towertalk@contesting.com
> Subject: [TowerTalk] Radials vs vertical height
>
> The importance of radials all depends on vertical height.
> If you can't put out much in the way of radials, you can
> still get excellent results by making your vertical longer
> than 1/4 wavelength and/or adding top loading. If this
> is doable at your QTH, you can get by with only a few
> radials and still get out very well because the radiation
> resistance will be considerably higher than 36 ohms.
> For some reason, most vertical users don't take advantage
> of this and fret over radials. There seems to be a knee jerk
> response of tuning the vertical to resonance, instead of tuning
> it below resonance and then bringing it back with a series capacitor.
> Only if you have a height limit problem (typically on the low bands) are
> you looking at a serious tradeoff between radials and efficiency. Yhen
> you might be looking a radiation resistance of only 5 or 10 ohms.
>
> One foot of extra height is worth many feet of radial wire.
> Think about it.
>
> Rick N6RK
Good points Rick,
That's why many people have good success with the inverted L. If it is made
longer than a quarter wave length the radiation resistance rises and a good
ground becomes less important but it seems few recognize that.
I mentioned long ago in this thread that a 1/2 wave vertical needs almost no
ground to work pretty well and most seemed to want to ignore it and continue
to bitch about how many radials you need or the antenna won't work.
73
Gary K4FMX
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