Hi Tom,
You said "Compared to a vertical, there could be 10-30 dB difference in
favor of a low dipole (less than 150 ft high) within a few hundred miles.",
and I was pretty much trying to make the same point but indirectly since I
don't have a dipole on 160 meters.
The original poster mentioned relatively short distance work on 160 meters,
and that is why I mentioned that a true vertical may not actually be his
best choice (he might actually go backwards in performance if he is trying
to work stations in adjacent states as an example).
Don (wd8dsb)
On Wed, Dec 2, 2015 at 3:04 PM, Tom W8JI <w8ji@w8ji.com> wrote:
> You are misinterpreting the model data by looking at the shape of the
>> pattern rather than the relative strength of the pattern at angles of
>> interest. Example -- the so-called "take off angle" simply shows the
>> vertical angle where the signal is the strongest. FAR more important to
>> look at the field strength at various angles as the height is varied.
>>
>
> Many people talk about and look at TOA, and it causes them to pick
> antennas that are actually worse just because the TOA is at the correct
> angle. :)
>
> If you look at a low dipole, it has just about the same gain as a low
> loop. Being a loop helps moderate impedance on harmonics, but not much else.
>
> I have 300 ft of height here. For the most part, a vertical did as well or
> better than a dipole at any height and distance. The exceptions were at
> sunrise or in magnetic storms, or within 50-200 miles (where a dipole below
> 150 feet works much better). Compared to a vertical, there could be 10-30
> dB difference in favor of a low dipole (less than 150 ft high) within a few
> hundred miles.
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