[TowerTalk] 75/80 vertical

[jim Jarvis]

Gregg,

234/f says that a quarter wave on 3.8 is 61.58 feet.

If it were me, I'd start putting in radials, and hook the thing up to  
the rig, or
an antenna analyser, to see what you've got.   Worst case, you may  
have to
go topside and drop in a 2' piece of tube.

25g should make perfectly fine connection between sections, properly  
bolted.
Adding jumpers won't make it measurably better, unless the tower was  
painted
before assembly.

I'm considering something similar, here, with 40' of 25g and a 24'  
section of 2" mast.

Jim/N2EA



Message: 8
Date: Fri, 20 Mar 2009 22:56:46 -0500
From: "Gregg Seidl" <k9kl at centurytel.net>
Subject: [TowerTalk] 75/80 vertical
To: <TowerTalk at contesting.com>
Message-ID: <B3933CD4A80D413BB0106C9BEF1F0C81 at K9KLStation>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
	reply-type=original

Well now that most of the snow has melted its time to finish last years
antenna projects!! My question is this: I installed 60 feet of Rohn 25
insulated from ground. I used the tapered top section as I'm going to  
use a
peice of pipe to "finish" the length.  I'd like it to resonate at 3.8  
Mhz.
About how much pipe do I need to add to make it work. I have one of  
Array
Solution AS-80 tuners. I will be using about 60-80 radials about  
60-100 feet
long. Tha way the tuner works is it needs to resonate at 3.8 or so  
and then
it switches in inductance to tune it to 3.5 and 1.8.
  Does Rohn 25 typically make a good connection between sections? I was
thinking about running a piece pf copper wire from bottom to top secured
with some copper-ox and circle clamps. Good idea or??  Thanks  Gregg   
K9KL