Topband: RDF

[Earl W Cunningham]

The method of using EZNEC to calculate RDF is new to me and looks like a
useful tool for evaluating receive antennas.

I modeled Pennant antennas in various configurations to see how their
RDFs compared.  I used real, high accuracy over "average" ground in all
models.  The elevation angle used for max gain was 30 degrees in all
cases.  Here are the RDF results, in worst to best order:

Single Pennant = 7.79 dB

2 broadside Pennants, 150' spacing = 8.71 dB

2 endfire Pennants, 135' spacing, 90 degree phasing = 8.87 dB

2 endfire Pennants, 135' spacing, 110 degree phasing = 9.34 dB

2 endfire Pennants, 135' spacing, 165 degree phasing = 10.74 dB

2 broadside Pennants, 315' spacing = 11.01 dB

2 endfire Pennants, 135' spacing, 180 degree phasing = 11.07 dB

4 Pennants in endfire/broadside, 315' braodside spacing, 135' endifre
spacing, 110 degree endfire phasing = 12.07 dB

The last one rivals a 2-wavelength Beverage wire.

73, de Earl, K6SE