Frank et. al,
The ground does indeed affect the Vf however different types of wires/cables
are affected differently and the only way to know for sure is
to measure the Vf yourself. I use old telephone cable ( C Rural wire) for my
BOG and it is distinctly different from the normal window line used on my
elevated Beverage or someone else coaxial BOG.. So you gotta get out of the
shack and do the leg (and sometimes brain) power to find the correct info.
Jim WA3MEJ
P.S. Frank to you have a soft copy of "Propagation Of High Frequency Currents
In Ground Return Circuits" (1934) that you could part with
Message: 1
Date: Thu, 1 Oct 2015 21:06:48 +0000
From: Chuck Hutton < charlesh3@msn.com >
To: " donovanf@starpower.net " < donovanf@starpower.net >, 160
< topband@contesting.com >
Subject: Re: Topband: BOG question
Message-ID: < BLU184-W5B98DC5B4BAC3B78FE70BFC4C0@phx.gbl >
Content-Type: text/plain; charset="iso-8859-1"
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
>
Long Live Seal Team VI
http://www.qsl.net/wa3mej/index.htm
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