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Re: [TowerTalk] Christman Phasing help!

To: "towertalk@contesting.com" <towertalk@contesting.com>, Jim Lux <jim@luxfamily.com>
Subject: Re: [TowerTalk] Christman Phasing help!
From: "R. David Eagle via TowerTalk" <towertalk@contesting.com>
Reply-to: "R. David Eagle" <kb8nnu@yahoo.com>
Date: Sat, 6 Sep 2025 21:51:09 +0000 (UTC)
List-post: <mailto:towertalk@contesting.com>
 Hi Jim,
I am going to remeasure the antennas tomorrow if the weather improves around 
here.  I somehow misplaced the numbers.  But anyways....The 2 quarterwave 
vertical sections I built out of 14G THHN held up by two HD spiderbeam poles 
mounted on 4x4's.  The antennas are spaced 1/4 wave aprat. The feedpoint is 
about 6ft off the ground so I could run 2 quarter wave elevated radials off 
each.  Currently, the radials are running parallel between the 2 antennas.  The 
antennas are mounted NE - SW along the edge of hardwood forest with no other 
metal near the antennas.  I wound a small impedance transformer this spring to 
hopefully take me from mid 30's to something closer to 50 but that didn't help 
much either.  I was considering going the route of putting together a small LC 
network....but then I would have to have a means of switching that as well from 
when I go Broadside to endfire......or maybe not.
DaveKB8NNU
    On Saturday, September 6, 2025 at 11:05:02 AM EDT, Jim Lux 
<jim@luxfamily.com> wrote:  
 
 
    


 
what did you expect to see?
What are the impedances you see at the two verticals,without the coax, and with 
the other antenna "open"

On Fri, 5 Sep 2025 23:55:52 +0000 (UTC), "R. David Eagle via TowerTalk" 
<towertalk@contesting.com> wrote:

Hello all,
Let me preface this by saying this - I am NOT a phasing expert by any means so 
I thought I would tackle a new antenna project this summer and maybe learn 
something....or lose more hair!  So any ways...I decided to put up a pair of 
phased 1/4 wave verticals and phase them via the Christman method.  Each 
antenna has 2 raised radials.  I ran across an article by W4NFR where he did 
exactly what I am attempting, BUT I am getting different results....naturally.  
I tuned each vertical to 7.100 exactly trying to get the lowest possible 
reactance on each.  I checked and double check the RG-213 71 degree delay line 
and the 84 degree feeds to the verticals.  Now, here is the puzzling part - 
when I put everything together in  my homebrew directional switch box, my 
resonant frequencies are considerably higher when I switch between Northeast, 
Broadside, and Southwest.  The resonant frequencies are near 7.450-7.500  where 
R=39 with X=6.
So I must be missing something here.....Anyone else had success with this?
Any help would greatly be appreciated!
DaveKB8NNU
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