>The last 25% of the horizontal portion would be over the house.
>I know this would change directivity but how would it effect ones
>health?
The only study linking non-ionizing radiation to health risks was
based on fraudulent data. Everything else shows unless you actually
heat the cells nothing happens. It takes an extreme amount of power
on low frequencies to heat someones tissues. The exposure guidelines
are VERY conservative, and you would be nowhere near safe limits with
that antenna.
> system. If you plan to use an inverted L antenna, I suggest to study
> an antenna with two parallel horizontal wires, one at the top of it
> and one at its base, even one meter above ground. Feed the antenna at
> the center of the vertical section.... and even if the vertical
> radiator is very small, I think you get a good radiator.
The idea elevating a feedpoint improves performance was probably
popularized by an antenna company who claims their elevated feedpoint
makes super performance. Unfortunately it is one of the worse
antennas available for low bands.
You can move the feedpoint around all you like, and efficiency will
not change unless you make a bad or poor feedpoint connection. It is
the distribution of current that can change efficiency, and that only
changes when you change the system's structure....not when you move a
feedpoint around.
For good efficiency an antenna either requires many radials or
counterpoise wires, very salty water, or to move the antenna at least
1/8 to 1/4 wl or more above earth at the closest point to earth. This
is even true for dipoles, and is especially true for any vertically
polarized antenna. Install a reasonable ground, and be done with it.
73, Tom W8JI
W8JI@contesting.com
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