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Ian Jackson[_2_] · October 12th 14, 08:43 PM posted to rec.radio.amateur.antenna

In message ,
writes
Ralph Mowery wrote:

wrote in message
...
I've done a lot of modeling with V's and inverted V's. Except for a slight
diffenence due to ground effects at low heights, there is no difference
between them.

As the angle goes from 180 degrees, i.e. a dipole, the impedance goes
down and and the pattern spreads out.

I have not played with the programs , but often wondered what the effect is
on antennas that are suported on the ends and the middle is dropped in a U
or V shape and not the inverted V shape. Many antenna books and articals
seem to show the flat top and inverted V paterns, but I have not seen any
with the actual V type.

Like I said, there is no difference in free space between a V and an
inverted V.

There are slight differences when close to ground.

Assuming it's a halfwave dipole, I would have thought it was better to
concentrate on getting the centre (where the current is) as high as
possible, rather than the ends. [Obviously this depends on whether you
have a suitable sky-hook available for and at the centre.] However, I
believe that there is at least one commercial loaded dipole (essentially
for portable use, I think) that has a short mast, and the ends of the V
are up in the air.

Also, regarding the radiation pattern, as the ends are dropped, doesn't
the signal that starts coming off the ends have an increasingly
vertically-polarised component?

--
Ian