The "Fan Dipole" is one of the worst antennas there is . . . in the eyes of
the neighbors.
Regardless of its technical characteristics, the neighbors think "it's ugly
and destroys the value of the neighborhood property." That's their biggest
disadvantage.
If you don't have neighbors or have neighbors who don't care, then you're
lucky.
Most of us do, and that's a show stopper for the fan dipole.
The second problem of the fan dipole is its weight.
The more dipoles, the more weight...which means a larger mast is required to
support them.
This costs more, usually a lot more, and requires more guying - which
creates a more obtrusive scenario for the neighbors.
A single wire dipole using small size wire can be supported on a lightweight
telescoping fiberglass pole.
The fiberglass pole can be spray-painted to match its background; green if
you have evergreens around, light grey if there is nothing around, etc.
This is about as inconspicuous as you can get with wires.
Openwire is nice but suffers from the same "neighbors problem" as the fan
dipole.
To our neighbors, openwire running through the air is ugly.
Guess who's side the XYL is on! :-(
Worst Case: (as I now have) "renting and living in the same house as your
landlord."
He lives upstairs and has patio and back yard, we live downstairs with the
patio in the front yard. We live on a mountain side so that works.
It was a hard sell to be allowed to put up any antenna at all.
Permission was granted for: "one pole, one wire, one hole" (in the wall for
the coax).
My 80m OCFD was the result of this dilemma. It was designed out of
necessity.
HERE'S A SUGGESTION THAT WORKS BETTER THAN THE FAN DIPOLE:
(Assuming you can put up 2 wires.)
Build two antennas:
1) Either an openwire fed dipole plus appropriate matchbox, OR an OCFD as I
referred to earlier.
2) An openwire fed vertical dipole, with 5 to 6m (16 to 20 ft. per side),
plus an appropriate matchbox.
The vertical dipole can be used to fill in the gaps (nulls) of the
horizontal antenna on the high bands. It also works nice for DX on 40m if
you can get closer to the 20 ft. length (per side). Making it longer than
20' destroys the 10m performance.
BTW, it fits nicely onto a 12m telescoping fiberglass pole.
LB Cebik wrote an article on the 2x 5m version of this antenna, entitled "A
Vertical Doublet for 30-10 Meters".
Here is his concluding statement:
"If you have the space and resources for a better antenna, by all means
use it. However, for
the ham with limited space and resources, a vertical doublet for 30 through
10 meters--based
on the 20-meter dipole--makes an effective antenna for general
communications."
My extension to this (i.e., adding one more meter per side) makes it a very
good 40m antenna, albeit at some loss in performance on 10m.
73 - Rick, DJ0IP
(Nr. Frankfurt am Main)
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