[Elecraft] K3 on motorboat.

[Barry]

First, electrical engineering is not a science, it's an art as 
compromises must be made. Fresh water is a terrible ground, so using a 
ground independent antenna is a compromise. Yes, a 1/4 wave antenna over 
ground will not be great for DX, but does allowm entering the 40 meter 
nets. Having said that, the antenna will be a 1/2 Wave on 20; that will 
lower the main lobe. You may not get the re-enforcement over fresh 
water, but it's more radiated power than using a vertical with a very 
poor ground system. We can debate the phenomena, but no mater a 
compromise is going to be required. Like I said at the top, EE is an art 
and not science and this artist has chosen to approach a solution swet 
this way. I'm quite sure there are other artists who may have other 
compromises.

73,
Barry
K3NDM


------ Original Message ------
From: "Jim Brown" <jim at audiosystemsgroup.com>
To: elecraft at mailman.qth.net
Sent: 6/9/2020 6:24:37 PM
Subject: Re: [Elecraft] K3 on motorboat.

>On 6/9/2020 3:13 PM, Barry wrote:
>>I counsel inverted Vs as they are ground independent.
>
>Not really -- the earth in the near field is lossy (including fresh water) and in the reflection from earth in the far field combines with the direct signal to produce the vertical pattern. Almost any horizontal antenna for 40M or lower that we can rig on a small boat will be a low one, so will be a high angle antenna, over fresh water, a lossy one. In general, verticals are better than than horizontal antennas over water, fresh or salt, because of the far field reflection, as long as a suitable counterpoise is provided.
>
>73, Jim K9YC
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