The only time I have verified EZNEC being different from my real world
measurements is usually because of some error I put into the model or
something I left out of the model. However I can't do comparisons of
high dipoles and verticals on 160 at my station because I don't have
them. I can look at data generated by others (who are likely to not be
in error) and check that with EZNEC. In the case of 160 (and only 160)
I can't get their results to agree with EZNEC. So I'm wondering if
there is some magic on 160 that says a vertical get a special advantage,
and what the heck is it?
EZNEC says a 300 ft high dipole on 160 beats a quarter wave vertical at
all elevation angles under 54 degrees even if I assume zero near field
ground loss for the vertical. Real world data disagrees.
By the way, this disagreement doesn't exist on 80 meters.
Jerry, K4SAV
RLVZ@aol.com wrote:
>
> Hi Guys,
>
> TT is tremendous- what a wonderful wealth of information is shared!
>
> I am NOT trying to stir up trouble here as I am very thankful for modeling
> software like EZNEC. But I'm hoping that the accuracy of modeling software
> will continue to improve.
>
> RadioIR (below) states how EZNEC is not always accurate.
>
> A few weeks ago, I posted an e-mail on how in dozens of side by side
> comparisons my single 40-m. 1/4 wave vertical near saltwater worked at least
> as
> well, if not better, than a new Cushcraft XM-240 Shorty-Forty at 90' in all
> directions the vertical looks over saltwater: Europe, Africa, and South
> America.
> Computer modeling indicated that the Shorty Forty should have about a 10dB
> advantage over the vertical with saltwater. (and the vertical has a minimal
> radial system: two 1/4 radials and a single 2" copper strap saltwater)
>
> My hope is that more actual side by side antenna comparison information can
> be used to improve modeling accuracy.
>
> 73,
> Dick- K9OM
>
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