[Antennas] eznec model for 2 meter co-linear please

[Richard (Rick) Karlquist]

The old VHF TV antennas operated on both the low VHF channels
and the high VHF channels with the same set of elements.  The
high band is roughly at the 3rd harmonic of the low band.
However, those antennas are log periodic dipole arrays.  Not
colinears.  Not Yagi's.

In your case, your 146 MHz elements will not resonate at
3 X 146 = 438, but rather will be a few percent higher,
as can easily be seen on EZNEC by modeling a dipole.
It is conceivable that the it might work out to cover the
440 to 450 band.  However, the element spacing will be all
wrong on 440, being 3 times what is needed.  It is simply
not going to work as a Yagi.  It might accidentally have
a few dB front to back ratio, but you should consider it
a rotatable dipole.  Of course, a dipole on the 3rd harmonic
even if matched, will have considerable sidelobes, again
as can easily be seen on EZNEC.

Rick N6RK

On 12/11/2016 9:22 PM, Jim Miller wrote:
> I am in Kindergarten on Eznec so do not know how to do much at all.
>
>
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> I would like to have a model for a 2 meter co-linear antenna to see how that
> is done.  Would someone send me a model  - 2m co-linear.
>
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> Really, I want to see what I am getting out near the ground when my old
> WinTenna 9209 is mounted at 40 feet above ground AND is there is any
> functional use of it when fed on 440 band.  SWR is totally reasonable but I
> can't imagine what is going on in the antenna.  It has to be really
> confused. Hi hi
>
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> Thanks guys es 73, Jim KG0KP
>