Topband
[Top] [All Lists]

Re: Topband: Antenna Question

To: "jim@audiosystemsgroup.com" <jim@audiosystemsgroup.com>, "topband@contesting.com" <topband@contesting.com>
Subject: Re: Topband: Antenna Question
From: Raoul Coetzee <raoulcoetzee@yahoo.com>
Reply-to: Raoul Coetzee <raoulcoetzee@yahoo.com>
Date: Mon, 9 Dec 2013 11:21:57 -0800 (PST)
List-post: <topband@contesting.com">mailto:topband@contesting.com>
Hi Jim and all,
I have been using a 16m vertical (T vertical ) with a limited amount o radials. 
My property is only 41m by 20m , so very limited space for
antennas, radials etc.
I got dxcc on 160m which many will say is easy, wait to try and get 300 
countries etc.Well, this was my own little achievement in the space I have,
the money I dont have :-) etc. 
Problem is, the antenna died in a storm, top loading wires broke off and a 
tower will go up in the same place of the old vertical.
Yes, I do work other bands as well!
So my dilemma is how to get a 12m tower up with a Mosely type 3 band beam, plus 
80m, 40, 30 dipoles attached to the same tower and load it up for 160m?All in 
the same space. The 3 band beam was locally made by a deceased Ham, it is very 
well build but I would like to model and optimize
it before putting it up.So if anybody has a Mosely T33, CA33 model for EZNEC or 
MMANA, please let me know.
So I am off 160m for the time being.
 
 
Regards,
Raoul ZS1REC
 
 
 
 
 
 

From: Jim Brown <jim@audiosystemsgroup.com>
To: topband@contesting.com 
Sent: Monday, December 9, 2013 8:59 PM
Subject: Re: Topband: Antenna Question


On 12/9/2013 10:47 AM, Ashton Lee wrote:
> The 43 foot antennas are very short (low inductance, poor efficiency) on 160. 
> Only my very best tuners will tune them… and tuning doesn’t make them 
> efficient, it only makes them not destroy the radio with reflected currents.
>
> The best solution is to top load a 43 food antenna and turn it into an 
> inverted L. Of course, if you have trees, a wire will do the same thing 
> without needing the 43 foot aluminum part.

Great advice. And, of course, any end-fed vertical needs radials or a 
counterpoise. A year or so ago, I did a tutorial presentation on 160M 
with limited space. Nothing original on my part, simply showing the 
fundamental stuff about how antennas work, and pulling together lots of 
excellent work by others.  http://k9yc.com/publish.htm

73, Jim K9YC
_________________
Topband Reflector Archives - http://www.contesting.com/_topband
_________________
Topband Reflector Archives - http://www.contesting.com/_topband
<Prev in Thread] Current Thread [Next in Thread>