[TowerTalk] Christman Phasing help!

[R. David Eagle]

Jim,
I finally had a few minutes to go back and measure the antennas at the feed point.  I found 1 antenna slightly off so I adjusted it so both are now relatively close.  Antenna A was R=32 X=9 and Antenna B was R=38 X=7 centered at 7.100.  I had several people recommend adding a choke at the feed point on each antenna. I may have to add some beads. Thoughts?  I also like the idea of implementing a simple LC network something like Gary NA6O suggested.  Now, I am second guessing myself and maybe should have gone a different route.  
DaveKB8NNU 
 


 
  On Sat, Sep 6, 2025 at 5:52 PM, R. David Eagle via TowerTalk<towertalk at contesting.com> wrote:   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 at 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 at 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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