snip
>The impeadance of a dipole in free space is about 72
>ohms at the center feed point which is why you can
>feed it directly with coax. Of course site conditions
>usually drop the dipoles impeadance quite a bit.
FWIW The impedance of free space (and a vacuumn) is approximately 377 Ohms.
It too is referred to as Zo and is a physical quantity. A horn antenna in
radar or microwave serves as a match from the feedline (waveguide) and free
space.
Jim de wd4air
>You can also feed the dipole with the higher
>impeadance open wire feeder and be ok because you are
>transfering power from a high impeadance source to a
>low impeadance load. The key point here is that the
>antenna is the load, not another transmission line.
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