Topband: K9ay loop not performing

[Dan Maguire]

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