[TowerTalk] Loop vs Dipole...I'm original "asker"

[Steve Hunt]

At the risk of "flogging this horse to death", but just to re-inforce 
Jim's point:
> Again, EXACTLY RIGHT. The missing data for the model are those things 
> you forget about when you build the antenna, or are too complex for 
> the program to compute.
In developing my new Broadband Hexbeam I consistently saw a small, but 
significant, frequency offset between what EZNEC predicted and what I 
measured on the prototype antenna. I even had Email exchanges with Roy 
Lewallen to see if he was aware of some problem with his software. He 
simply encouraged me to make sure I had taken all factors into account 
in the model.

Eventually I realised that I had failed to include in the model the 
small connector blocks which I used to join the tips of the wire 
elements to the insulated spacer cords.  They were adding significant 
"end capacity". Once I included them, the frequency error disappeared 
and I got even better correlation between the F/B predictions and the 
measured results.

Moral: you can't expect EZNEC to take into account the things you don't 
tell it about :)

73,
Steve G3TXQ