At 10:45 AM 4/25/2006, Peter Sundberg wrote:
>You can download a program that does all calculations for you, be it yagis,
>dipoles, verticals or what..
Very slick... and makes it easy to check across bands
Does it take into account nearfield effects for low gain antennas?
e.g. for a dipole or inverted V close to the ground, it's the ends that
present the RF safety problem, not the far field radiation
Another problem I ran into was with a phased array, where there's a lot of
circulating power among the elements. I suspect that for any
superdirective antenna (e.g. a Yagi) this might also be the case, since
there's energy stored in the near field.
>Have a look at http://www.sm2cew.com/download.htm
>
>You will find the VK3UM Site and Radiation Calculator version 5.1
>(EMRCalc.exe) if you scroll down the page a bit.
>The program does not need an install, just run the EXE-file.
>
>When it comes up it is in VHF/UHF/SHF mode, click a small box marked "HF"
>in the "Frequency" box to get the HF options and antennas.
>
>Different radiation limits (standards for different countries) can be chosen.
>
>73/Peter SM2CEW
>www.sm2cew.com
>
>
>
>
>
>
>At 23:56 2006-04-24 , Bill Tippett wrote:
> >N6KJ wrote:
> >
> >>Actually, what I'm trying to do is figure out the radiation pattern on
> >>the ground. Why? I'm doing RF Exposure calculations and rather than
> >>assume the worst case exposure on the ground based upon the gain of
> >>the antenna, I'd like to know what the actual gain is below the
> >>antenna on the ground. I'm assuming it will be considerably less.
> >>For example, what is the gain of my antenna at a 45 degree angle in
> >>front of my yagi, but on the ground?
> >
> > OK I understand now. Here is what I
> >would use if I were you:
> >
> >http://n5xu.ae.utexas.edu/rfsafety/
> >
> > 73, Bill W4ZV
> >
> >
> >
> >
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