The current in an end fed half wave "monopole" is virtually
identical to the current in a center fed "dipole". Although
the feed systems are different, the results on the air will
be extremely similar. Each feed system has its advantages
and disadvantages, but they are just implementation details.
Another example: a so-called "co-linear array" has pairs
of half wave elements end fed: two half waves in phase.
You can also use a "corporate feed" to drive the two half waves
in their respective centers as "dipoles". These are essentially
the same array, just different feed implementation. There is
no fundamental difference.
Rick N6RK
Rob Atkinson wrote:
> <<<A 1/4 wave 80m vertical series fed on 40m is nothing else then a halve wave
> vertical on 40m which was questioned about.>>>
>
> No, the question had to do with one half wave length DIPOLEs,
> vertically and horizontally polarized. They may be symmetric or
> asymmetric but a DIpole has two poles right? a conductor fed at the
> end (base fed vertically polarized in this case) that is 1/2 wave
> length against a ground screen is not a DIpole, but it IS 180 degrees
> long (tall) for some frequency.
>
> <<<A vertical dipol can be fed at one end, center feed is no must.>>>
> Center feed is not necessary; feed point can be off-center, but it's
> NOT a DIPOLE if fed at one end; what you have is a MONOpole which is
> not what the question was about.
>
> <<<Radials are useful below ALL kinds of vertical antennas anyway.>>>
>
> Especially on sand. : )
>
> 73
>
> rob / k5uj
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