[TowerTalk] Antenna modeling question

[jimlux]

On 9/4/16 8:50 PM, n0tt1 at juno.com wrote:
> Gents,
>
> I'd like to build a 40m phased array "inside" my 160m
> receiving-only 9-circle and I want to check for any
> interaction between the two antennas.
>
> I have the layout in EZNEC 6, but I'm not sure how
> to "feed" the 160m array.  Do I let it "float", ground the
> elements or what?
>

Well, what's the antenna element connected to when you're not using it? 
A piece of coax with no termination? A termination?
You can model that directly.

When I'm looking for interactions, I set the model up and then connect 
and disconnect the element or structure from ground or a load and see 
what happens to the antenna being modeled. You can look at the feedpoint 
Z and see if it changes, or look a the pattern to see if it turns weird.

it's the "does this make any change" question that tells you if there's 
interaction.