Frank:
I believe there is a large influence of height above ground on VF.
>From a theoretical basis, this has been "known" since Wise's classic paper
>"Propagation Of High Frequency Currents In Ground Return Circuits" (1934).
This was experimentally verified in the Litva and Rook report from the CRC
(Canada), and compared with theoretical results.
These guys didn't extend their calculations to right-on-the-ground antennas.
The attached (if it gets through the server) is from a spreadsheet of mine
based on the Wise equations. The influence of height on VF is very very
pronounced.
Chuck
> Date: Thu, 1 Oct 2015 11:23:16 -0400
> From: donovanf@starpower.net
> To: topband@contesting.com
> Subject: Re: Topband: BOG question
>
> Hi Art,
<CLIP>
> Signals arriving at the BOGs are not travelling in the ground, therefore
> their velocity of propagation (Vp) is unaffected by the ground.
>
> 73
> Frank
> W3LPL
>
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