As others have said, a good *RF* ground is a requirement. Here's a comparison
of modeled elevation patterns for a K9AY loop with a very good (low impedance)
RF ground vs one with a very poor (high impedance) RF ground.
https://i.postimg.cc/N0MqJg0x/image.png
The trick to modeling a good ground while at the same time using EZNEC "High
Accuracy" (Sommerfeld-Norton) ground is explained in EZNEC Help section
"Connecting to High Accuracy Ground".
For AutoEZ users, *right*-click on http://ac6la.com/adhoc/K9AY_Loop.weq ,
choose "Save file", download to your computer, then use the AutoEZ "Open Model
File" button. The K9AY_Loop.weq model makes it easy to adjust the length of
the very low height radials which are used to simulate a good ground
connection, as mentioned in the EZNEC help.
Dan, AC6LA
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