[TowerTalk] HFTA

[Cqtestk4xs at aol.com]

Testing with HFTA at different heights and stack separation, we found  that 
the
best heights are 18/21/24 meters, in order to cover with the  best gain and
angles the wave angle of arrival stats.
Obviously, that is  quite a short separation compared with the range of 
stack
separations that is  normally used.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
There is one warning about HFTA that everyone who uses it should  know.  
N6BV says that it can give false gain readings if the antennas are  to close 
to each other (less than 1/2 wavelength).  Obviously, the 3 meter  separation 
is way less than 1/2 wavelength.
 
I went through the same stuff when I modeled my three high stack of  
KT36XAs.  I got all kinds of great gain with only 1/4 wave spacing, but it  was 
all make believe.
 
Bill KH7XS