[TowerTalk] EZNEC question

[Chris Adams]

David Clemons wrote:
> 
> Hi,
> 
>         I am trying to model a 4-wire lazy-V array on EZNEC.  The array
> (as designed by K3LR and others in August 1994 QST) uses RG8X feedlines
> which are 153.45 degrees electrical length.  One feedline is chosen at
> the switchbox, and both the centers and shields of the others are totally
> disconnected from each other and ground.  Thus the feedline lengths
> together with the wires act as a reflector

------- snip


Dave,

I think EZNEC will model the antenna ok.  It will take into account the
effect of the transmission line being open circuited.  That is... the
effect of an open circuit transmission line being reflected through
153.45 electrical degrees.  What it won't take into effect without
additional work is actual currents running on the outside of the coax
"received" due to the effects of the transmitting element.

I have not done so, but I know Roy mentions in the manual running a wire
in parallel with the coax to take into account the induced current. 
Which brings me to a question, if I visualize this array correctly, (my
Aug 94 QST is in the storage locker) do you need a balun to feed the
individual elements correctly?

At anyrate, I hope this sheds some light on your question, if not, I'm
sure others can do so more eloquently then I!

73's

chris, n4vi

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