I have created various Flag models to investigate the effect of size and =
height on the pattern.
The MINNINEC models show that a Flag elevated up to a 1/4 wavelength has =
a very desirable low angle pattern. The "normal" high angle lobe which =
exists for close to the ground Flags becomes depressed as the height =
increases. It seems as though this could be a very desirable rotatable =
rx antenna if installed at the top of the HF or 160m TX tower. =
Interaction with a near-by resonant structure will pose problems =
however.
The models also show that smaller size flags preserve the usual F/B =
pattern. These smaller size flags would be easier to build rotatable =
and install on smaller "city lots". Unfortunately the gain is way down =
necessitating good pre-amps, feedline isolation and separation from =
resonant TX antennas.
I have posted these models at: http://www.qsl.net/ve6wz/FLAGindex.htm
I would like some opinions/comments on these models.
73 de Steve VE6WZ
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