G3TXQ wrote: Are we sure we're looking at the EZNEC results carefully
enough.
If I compare a 160m half-wave at 300ft with a ground-mounted
quarter-wave vertical, over average ground, the vertical has the
advantage at take-off angles under 10 degrees by as much as 8dB.
Well Steve it's obvious one of us is not looking close enough. I can't
get that. Are you sure you're not using a perfect ground for the
vertical? When I said no near field ground loss, that implies a Mininec
ground.
Here is some data. Tell me which you think is wrong.
A half wave dipole at 300 ft (260 ft long), 1.84 MHz, average ground.
Elevation Gain
26 deg __ 8.3
15 deg __ 6.46
10 deg __ 3.77
5 deg __ -1.7
Quarter wave vertical over Mininec ground and no added near field ground
loss (which is guaranteed to be better than any real vertical), 128 ft
tall, 5 inches diameter.
Elevation Gain
26 deg __ 1.2
15 deg __ 0.81
10 deg _ -0.29
5 deg __ -3.36
Steve Hunt wrote:
> Jerry,
>
> Are we sure we're looking at the EZNEC results carefully enough.
>
> If I compare a 160m half-wave at 300ft with a ground-mounted
> quarter-wave vertical, over average ground, the vertical has the
> advantage at take-off angles under 10 degrees by as much as 8dB.
>
> That of course is in the dipoles favoured direction. At low angles the
> dipole is exhibiting a front to side as high as 18dB, so the vertical
> would have a considerable advantage at low angles for much of the
> azimuth. In the dipole's worst direction the vertical beats it for all
> angles below 66 degrees.
>
> And anything better than Average Ground favours the vertical even more.
>
> Steve G3TXQ
>
>
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