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43' vertical monopoles sometimes are used with an auto-tuner at their input as radiators in the ham bands from 40m through 10m, but are any performance compromises required to do that?

Richard Fry
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While using a 43' vertical monopole as a Z-matched radiator on the upper ham bands through 10 meters can make the transmitter happy, it has considerably less gain/usefulness on 10 meters than a typical Ground Plane antenna installation does for the greatest range, single-hop DX contacts from the important elevation sector below about 25 degrees (see following graphic):

enter image description here

Richard Fry
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    Very interesting. Thanks for this analysis that, as you did, can only be performed properly with NEC-4. How much does the 43-ft monopole's performance improve if insulated radials are simply laid on the ground, rather than being buried? – Brian K1LI Jul 15 '20 at 13:05
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    Negligible change, based on previous studies I did using NEC4.2 to compare insulated vs.uninsulated radials (other things the same), – Richard Fry Jul 15 '20 at 13:33
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    @BrianK1LI why would NEC-2 have been insufficient for Richard's analysis? – rclocher3 Jul 15 '20 at 14:53
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    @rclocher3 NEC-2 doesn't model buried conductors. – Brian K1LI Jul 15 '20 at 17:11