Topband
[Top] [All Lists]

Topband: 160m vertical saltwater grounding

To: "topband@contesting.com" <topband@contesting.com>
Subject: Topband: 160m vertical saltwater grounding
From: Robert Fanfant <rfanfant@hotmail.com>
Date: Wed, 8 Jan 2020 22:30:05 +0000
List-post: <mailto:topband@contesting.com>
Am looking to activate a location with very limited space surrounded by ocean. 
Think of a small rock surrounded by saltwater/ocean.  The vertical will be a 
tall 60’+ fiberglass pole and made to resonate on 160m. I would like a way to 
reduce the required space of the 160m antenna radial field due to the limited 
physical space available. The vertical will be located at the waters edge, or 
even possibly over the oceans surface. At the feed point, will be a choke 
designed for 160m. We should also assume maximum power of 1.5KW being fed into 
the vertical and the activation will be for a 2 week duration of time.

One idea that came up is to use a floating piece of conductive material as the 
verticals counterpoise. Specifically,   a thin conductive plate designed to 
float on the oceans surface. From the antenna’s feed point, will be a short 
length of  ground wire say about 6’ long,  to this conductive plate.

Question(s):

  1.  Is it possible to just use the ocean as the ground plane / counterpoise ? 
That is, can this idea work?
  2.  If so,
     *   How do I determine the required square footage/size of the plate?
     *   What material should be used as the conductive plate? (Nickel, copper, 
aluminum, etc..? )The thought here is to make this plate as light as possible, 
yet effective. It  will need to last the duration of the activation (~2 weeks) 
in/on saltwater, it needs to handle 1.5KW at the feed point, and likely exposed 
to air and saltwater as it floats on the ocean surface.

-rob N7QT



Sent from Mail<https://go.microsoft.com/fwlink/?LinkId=550986> for Windows 10

_________________
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

<Prev in Thread] Current Thread [Next in Thread>