Steve Hunt wrote:
> Denny,
>
> Do you have a specific Cebik article in mind?
>
> I'm pretty familiar with his work and I just re-read his 5-part article
> on modelling 160m verticals, but I can't immediately see anything that
> suggests the modelling is significantly in error.
>
Back in the late 60's through the 70's I ran a contest style station
with separate rigs and antennas on each band. I ran a 5L KLM on 20, 6L
on 15 and a 7L Wilson on 10. I ran verticals, both single and
co-phased, on 40 along with 40' high dipoles and could switch back and
fourth. There was always (at night) some distance (which varied) where
the vertical or verticals would surpass the dipoles. Sometimes the
difference was substantial. Typically the difference on long haul was
about one S-unit, however the verticals also discriminated *against*
stateside QRM unless it was close. This meant DX stations that were in
the noise on the dipole(s) would often be several S-units above the QRM
and easy copy when I'd switch to the vertical(s).
Much depended on band conditions and the present ARRL Antenna handbook
goes into how the best angle changes through out the day and sunspot
cycle. It also covers the percentages at to how often each angle is best.
Antipod? There are none from Michigan unless you are in boat.
As for the modeling results, they do not mirror my experience with
verticals while the results I've seen on here for different heights of
Yagi antennas do. No I wouldn't expect exact matches on a day to day
basis, but I would expect them to echo the trends. That they do not,
suggests to me something is missing.
73
Roger (K8RI)
> Regards,
> Steve G3TXQ
>
> Dennis OConnor wrote:
>
>> Steve, I agree that is what a Mininec model likely shows...
>> A model is not the real world...
>> A good read of Cebik in this subject will give additional information...
>> ...
>> And while my example may be a bit overwrought, it mirrors real world
>> performance...
>> The whole point of my post is that real world GP vertical performance is not
>> as dismal as a Mininec plot suggests...
>> And a low, horizontal antenna is not as necessarily as good at low angles as
>> Mininec suggests...
>>
>> cheers
>> denny / k8do
>>
>>
>>
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