On 12/19/2014 2:25 PM, Steve wrote:
> 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
Hi Steve.
I have forgotten but doesn't the alpha delta have ladder line as well?
I placed an order this morning for the true talk wa2nan style g5rv since
it consistantly gets the highest ratings on eHam and is built like a
brink well you know grin!
A friend has one and has had it up for over 7 years high up in the
mountains in upstate new york.
With all the snow and ice up there it has never come down so am ginving
that one a try.
I worried abouth the mesh holding more snow water and ice then a plain
wire. Thats what kind of scared me away from it.
I believe I may live to regret that decision but we shall see.
Don
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