On 1/21/19 11:33 AM, Jim Brown wrote:
On 1/21/2019 11:23 AM, Edward Sawyer wrote:
One thing that HFTA does NOT do well is answer the question about
stacking
from a "max gain" perspective. EZNEC will tell you the best design for
stacking yagis for max gain in a direction however HFTA will tell you
what
the right height for those yagis are or if the stack is even the
strongest
signal under typical approach angles.
Right. HFTA models the performance of individual dipoles used alone, not
in combination. When you select a Yagi, it simply adds gain.
Correct me if I'm wrong, but I think it also changes the effective
vertical beamwidth of the point source radiator (in proportion to gain
or sqrt(gain) or some rule). that is a 2.15 dBi dipole has a vertical
pattern that is uniform gain, but a 10 dBi Yagi has a vertical pattern
with some significantly smaller vertical height.
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