I've been busy lately modeling a variety of 160 meter antenna's on EZNEC
3.0. For ground type I used real minimec and ground description
(conductivity) medium, frequency 1850 kc. From what I understand real
minimec approximates 32 1/4 wave radials. If you antenna modeling
professionals see any discrepancies in my data, I'm still learning how to
use the program.
1/4 wave L/ 128 feet long/ takeoff angle 20 deg.
1/4 wave L/ 64 feet up 64 feet out/ takeoff angle 25 deg.
3/8 wave L/ 64 feet up 128 feet out/ takeoff angle 60 deg.
1/2 wave L/ 64 feet up 192 feet out/ takeoff angle 90 deg.
1/2 wave T/ 126 feet up 252 foot flat top/ takeoff angle 25 deg./ gain 2.75
db
*1/2 wave T/ 51 feet near ground 75 feet up 252 foot flat top/ takeoff angle
30 deg./ gain 2.59 db
1/2 wave T/ 75 feet near ground 51 feet up 252 foot flat top/ takeoff angle
30 deg./ gain 2.54 db
1/2 Square/two 126 foot verticals with 252 foot horizontal phasing wire/
takeoff angle 25 deg./ gain 4 db
*=My present setup
73,
Thomas Giella, KN4LF
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