[TowerTalk] Half-square antenna question

[Gareth Crispell]

stu wrote:
> 
> I was looking at some drawings of half square antennas and while most
> articles said the bottom legs could be bent around without losing much
> gain I am wondering how much effect moderate drooping or bending between
> supports of the top horizontal part it would take to degrade
> performance? I don't have any 3 supports near a straight line so it
> would be fairly dog legged.
> 73' Steve KG8TX
> 
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You only need two supports for the half square. The "bottom legs" are
vertical radiators and should be as close to straight up and down as
possible. Think of this antenna as 2 quarter wave verticals phased by an
electrical half wave. I would put as little sag as possible in the 1/2
wave horizontal. You can anchor the bottom of the verticals with fishing
line tied to a cinder block so they don't wip around in the wind. The
bottoms only need to be about 6 to 8 feet off the ground. Tune to
resonance with this ratio. For every inch you cut from the feed side
vertical - cut 3 inches from the far end. Bring the feed line away at a
sharp angle so the horizontal part does not electrically "see" the
feedline. Darn good antenna and cheap to build. Low lift angles. 

de N1MSV
-- 
                                                           
                                      
                                                      
.....at the dawn of the New Age of Man,                  
     they will abide with us.                          
     Their glory and fire will burn like            
     sparks among the stubble!                       
                                                         
 Gareth

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