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[TowerTalk] Radial "FAN OUT" and vertical mast mounting

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Subject: [TowerTalk] Radial "FAN OUT" and vertical mast mounting
From: (Pat Rundall)
Date: Tue, 19 Feb 2002 12:52:33 -0800 (PST)
I have a brand-spanking-new-still-in-the-box Butternut
vertical that I'm planning on installing in the next
few weeks. Because I have a 4' chain link fence around
my back yard, I'm thinking that a short mast-mount
might be the best solution. An approx 10' mast should
help get it in the clear.

Anyone have tips on mounting a vertical like to
Butternut on a mast? Specifically...

- What did you use for a mast? Is it guyed? Is the
antenna guyed?
- Any gotchas in attaching the antenna to the mast?
- How did you handle radials? The Butternut manual
states "If a metal mast or tower is used to support a
vertical antenna all radials should be connected to
the mast or tower at the ground connection of the
antenna feedline." I understand that the mast must be
detuned. Should it effectively look something like
this (excuse the ascii art)?

            || B'nut
       c|-|-||]  clamp
        | | ||\r
        | | || \r
        |M|     \r
adials @ 45 degrees
        |T|        \r
        | |         \r

- If the above drawing is valid, I'd probably run
radials like this (overhead view):

              |  /
              | /
              / \r
             /   \r
            /     \r
      -----O       O-----
          /|       |\r
         / |       | \r
        /  |       |  \r

Again sorry for the crude ascii art but "M" is the
antenna itself, and "O" is where the radials actually
hit the ground (dropping at 45 degrees as above). What
I'm getting at here is that I'd like to "fan out" the
radials from just three points (rather than drop a
radial from the antenna itself). 

This "radial fan out" factor is something I've not
seen discussed here. Pros? Cons? I know that, in
general, more is better when it comes to radials. But
is radial fan out something to consider or is it
effectively the same as using random length radials?

Comments are appreciated.

Pat N0HR

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