fraz1 wrote:
>Hello....
>
>I'm going to pick brains once again. I am familiar with the antenna models
>for these antennas. Does anyone have actual comparisons of a Delta Loop and
>1/2 wave Dipole on 40 and 20 meters? A top height of 70 feet can be achieved.
> The Loop can be Delta or any other Loop configuration; vertical or horizontal
>feed. In short, I'm trying to determine if any Loop configuration offers a
>real advantage over a high 1/2 wave Dipole. Again, I know what the models
>say....what was/is your actual experience, please?
>
>Thanks, and 73........... John K4NP
>_______________________________________________
>
>
I'm curious why you would ask such a question.
1. Maybe you are trying to determine if NEC models predict real world
experimental data. If so, you aren't going to get that from an "I built
one and it works great" answer. To even get something close you need a
very controlled experiment, an antenna constructed on a test range with
a fairly accurate estimate of soil characteristics, an expensive
measuring system mounted on a helicopter, and make 3D plots of field
strength. You won't get that information from anyone on this reflector.
2. Maybe you are trying to verify that your models are correct. If so
then just go to Cebik's website and model the same thing and compare
results.
3. It seem as if you have the best answer already and you are asking for
something less reliable. It is possible to gain some information about
two antennas by doing A/B testing as long as you know all the data about
the two antennas. You can also draw some quick conclusions when the
difference is very large. In the case of these two antennas it is much
more difficult since the performance should be close. If someone
provides you with dB gain difference numbers, covering all azimuth
angles for both antennas, and average dB numbers for stations in various
locations (since you can't control the signal arrival angle), along with
detailed construction details for each antenna and a description of any
other antennas in the vicinity, then maybe you can draw some
conclusions. You are not likely to get that information either.
4. Maybe you would just like to promote an antenna discussion just for
the heck of it. Sure, have at it. I threw my 2 cents in.
Jerry, K4SAV
>
>
>
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