Don,
JMO, don't discount the AlphaDelta so quickly. Don makes very durable
antennas, and you should be able to match it with a tuner, since it is a bit
shorter on 80 than a inverted vee or dipole cut for 80/75 meters.
I don't think the mesh will make it much more visible.
I've had issues with some of the G5RV iterations because of the need to keep
the 300-ohm stub away from other objects. I also had a bit more TVI when I
used the G5RV years ago.
Steve, K8SP
----- Original Message -----
From: Don Breda
To: [log in to unmask]
Sent: Thursday, December 18, 2014 3:42 PM
Subject: Re: Alpha Delta info - response to query
Thanks Dave. Again that was extremely helpful.
I will probably rule out the alpha delta even though I think it has a
lot going for it.
I suspect up in the air its more visible then some other wire
configurations and that is a factor here.
I also feel thtat the 3 wires along with the mesh grid may be more
likely to hold on to water and snow and ice in the winter so I think for
those reasons right or wrong I will probably consider ruling it out.
Haven't made a final decision yet though and it is a good antenna by all
accounts.
Don
On 12/18/2014 3:27 PM, David Weigel wrote:
> Hi Don:=20
>
> Others may better explain the Alpha Delta DXCC multiband =
> dipole
> antenna better than I, but here=92s my response to your questions. =20
>
> The DXCC model has 3 dipole insulated wire elements of =
> different
> lengths coming out of the Alpha Delta center insulator. On each side =
> of
> the center insulator emerge 3 wires for the various bands covered by =
> this
> antenna. On each side there is one 41 foot length wire that covers the =
> 80
> meter, and 40 meter bands. The 40 meter length of this wire is utilized =
> for
> 15 meters, based on a 1/3 wavelength harmonic. Aditionally, there is =
> one 16
> and =BD foot wire coming out of each side of the center insulator for =
> the 20
> meter band. There is also one 8 foot length of wire coming out from =
> each
> side of the center insulator to cover the 10 meter band. The 10 meter =
> and
> 20 meter dipole wires are laced through a mesh like =93grid=94 for =
> lateral
> support, this mesh also connected to the center insulator. There is,
> therefore, no requirement for the ends of the 10 meter and 20 meter wire
> elements to be supported or tied to a tree or a pole, etc., because they =
> are
> supported in space by the mesh grid. The two 41 foot wire dipole =
> lengths
> are laced through the upper edge of the mesh grid, and serve as the =
> lateral
> support for the mesh grid and the 10 and 20 meter wire elements that
> achieve lateral support by being laced through the mesh grid. Thus, the
> placement of the 41 foot wire elements of the dipole serve to provide a
> similar alignment or direction of the 10 and 20 meter dipole wires as =
> they
> are in parallel, directly below the longer 41 foot wires extending away =
> from
> the center insulator. =20
>
> My DXCC arrangement works very well on 40 meters and 20 =
> meters,
> not requiring a tuner. 10 meters may or may not require the use of a =
> tuner,
> depending upon frequency chosen. Same goes for 15 meters. This =
> antenna
> (mine, anyway) requires the use of a tuner for 12 and 17 meters...I =
> don=92t
> believe that it was designed for these bands... But on 75/80 meters, I
> absolutely am required to use an external tuner, and the fine tuning is
> critical to achieve low s w r for me on this band. Even tiny little
> adjustments of the external tuner on a given frequency in the 75 meter =
> band
> causes s w r to jump. Others users of this antenna may not have this
> experience on 75/80 meters. However, one of the 41 foot wire elements =
> of my
> dipole terminates within about 12 feet of the metal roof on my house, =
> which
> may be throwing a fly into the ointment. I do get good signal reports =
> on
> 75/80 meters as well as 40 and 20 meters, the bands that I most =
> frequent.
>
>
> I hope that description helps to answer your questions. =
> This
> missive isn=92t necessarily sent to steer you in one particular =
> direction, but
> rather to describe the structure of the dipole and a bit of my personal
> experience with it. =20
>
> Regards,=20
>
> =
> Dave
> Weigel KD4JEZ
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