[TowerTalk] HFTA and diferent bands antennas

[jimlux]

Jorge Diez - CX6VM wrote:
> Hello,
> 
>  
> 
> I am trying HFTA, really very interesting the info from it.
> 
>  
> 
> I model for different antennas, also for a stack of monobanders.
> 
>  
> 
> BUT, how can I add a different antenna to this model?
> 
>  
> 
> For example I modeled a 3 yagi´s for 10 mts stack. I want to know how it
> will be affected if I add a 20 mts monobander in the same mast where I have
> the top 10 mts yagi. It´s possible with HFTA?
> 


HFTA doesn't model antenna:antenna interactions, which is why the user 
instructions caution about putting antennas too close together. (because 
at small distances they DO interact, and HFTA ignores it)

So, to find out what will happen to your pattern, you need something 
like NEC.  Of course, NEC doesn't deal with the terrain effects.