Oops. I knew 6dB figured in there somewhere, but I thought it was due to a
dipole being 3dB over an isometric radiator in free space, then a dipole
over ground being 3 dB over a dipole in free space (i.e., 3dB + 3dB = 6 dB.)
Both recollections were wrong. The gain of a dipole over an isotropic
radiator in free space is 2.14 dB, while the far-field reflected wave adds
another 6dB, for a total of 8.4 dB.
That's what happens when I try to remember this stuff off the top of my
head. I should have checked the Antenna Book before hitting Enter!
73, Dick WC1M
> -----Original Message-----
> From: Dave Hachadorian [mailto:k6ll@juno.com]
> Sent: Friday, September 17, 2004 11:57 AM
> To: towertalk@contesting.com
> Subject: Re: [TowerTalk] GPS receivers
>
>
>
> On Fri, 17 Sep 2004 11:04:29 -0400 "Dick Green WC1M" <wc1m@msn.com>
> writes:
>
> > Most of you are familiar with the fact that the gain
> > of a
> > dipole over real ground is increased by about 3 dB over a dipole in
> > free
> > space.
>
> Make that 6 dB.
>
> Dave Hachadorian, K6LL
> Big Bear Lake, CA
>
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> .
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>
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