It appears to me the 'forked radial' may have merit under vertical antennas
taller than 1/4 wave, where the maximum current appears higher than the base
and where the maximum reflected ground current may therefore be away from the
base. This will be quite noticable for a 1/2 or 5/8 wave vertical. However,
I haven't confirmed this by reference to any expert nor have I attempted to
model it with EZNEC. I need to learn how to correctly model ground radials
with EZNEC, hopefully in the ARRL course on modeling.
Many references (ARRL books on antennas and others) report that a given
length of wire for radials is used most effectively by putting a large number
of shorter radials in the area near the base, where the ground current is
highest. This becomes more advantageous under antennas shorter than 1/4
wavelength.
73 de WOØW
Bill Otten wrote:
> Frankly, I think the 'forked radial' idea has merit. In my situation I'll
> use the method in grounding my tower. I have plenty of 1.5" and 2" solid
> copper strap, plenty of ground rods too.....but my backyard real estate is
> lacking IF I run the ground straps from the tower in a straight line. At
> some point I get to where the ground rods are "overlapped" in coverage,
> something Polyphaser mentions against. If, however, I fork the straps past
> the point where overlap would occur, I can utilize more of the backyard to
> 'saturate' the ground if a strike happens.
> Any opposing viewpoints on this??
>
> Bill KC9CS (still enjoying the afterglow of working the TI9M Cocos Island
> DX group on 160M sideband last night at 2:30 am with 100 watts)
>
> ----- Original Message -----
> From: "Pat Rundall" <dxmonger@yahoo.com>
> To: <towertalk@contesting.com>
> Sent: Wednesday, February 27, 2002 3:04 pm
> Subject: [Towertalk] Radial "fan out" summary
>
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