Well, actually, on modeling that is what convergence testing does for you,
You take the models with the best approximation of real world earth
conditions etc, and then you test for the practicality of the design
solution that emerges.
Even text book antenna formulas are for free space or idealized earth
conditions and vary widely from some real installations. With time and
experience, an antenna user knows to cut the wire ends long to be able to
fold back to his desired resonance point, to think out various ways to route
feeders and position antennas to avoid other conductors and get his pattern
into the desired directions all with safe installation.
No one antenna design does all things to all operations.
Start from the best set of assumptions and conditions you can identify and
have the extra feeder length to shift match point, extra wire length on
doublets, and adequate support height above the station or rig to avoid RF
in the shack and one should be able to find a very workable antenna set up.
Nominally balanced antennas such as half wave dipoles and similar contribute
almost built in good performance on all considerations.
73,
Stuart
K5KVH
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