My error Jim, I meant quad. Thanks.
-----Original Message-----
From: Jim Forsyth [mailto:jim@af6o.com]
Sent: Tuesday, September 22, 2015 10:01 AM
To: Matt
Subject: Re: [TowerTalk] FW: 80 meter wire antenna question
He doesn't have a delta.
On 9/22/2015 1:07 AM, Matt wrote:
> I believe that if you are feeding the delta at the middle of one side,
> then the antenna's radiation pattern is vertically polarized and the
horizontal
> parasitic won't do anything for you. I made a quick NEC model just now
> that indicates a vertical placed behind the antenna could be tuned to
> act as reflector, producing about 10 db F/B and about 3 db forward
> gain optimizing for length only - the performance did not seem to be very
sensitive to
> position. An interesting idea might be to explore one on either side,
each
> length-tuned as a director, then add switchable loading so that one
> would act as director and the other as a reflector with 180 degree
switching....
> one could also just build a pair of phased verticals for the same
> effort I guess...
>
> FYI about 10 years ago I built something similar for field day using a
> 40m wire vertical hung from a tree with a parasitic V-shaped vertical
> wire dipole reflector behind it - kind of like a vertical jungle job
> except that I could move the tensioning rope almost 360 in a circle
> around the vertical radiator to change the direction of the pattern since
the spacing was fixed
> by the top support rope which was shared with the vertical. Anyway, the
> antenna worked very well and I made over 750 QSO's on 40m that evening
> just following the propagation.
>
> Hope this info is useful & good luck on your project!
>
> 73
> Matt
> KM5VI
>
>
>
> Interesting ideas though.
>
> -----Original Message-----
> From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of
> Tom Osborne
> Sent: Monday, September 21, 2015 11:13 PM
> To: towertalk@contesting.com
> Subject: Re: [TowerTalk] 80 meter wire antenna question
>
> If you get some answers directly sent to you, I'd sure like to see
> what they have to say about this. Thinking of doing something like
> this with a
> 40 meter delta loop. 73
> Tom W7WHY
>
>
>
> On Mon, Sep 21, 2015 at 6:25 PM, Dick Allardyce (N4RA) via TowerTalk <
> towertalk@contesting.com> wrote:
>
>> Hi all,
>>
>>
>> I need some advice about a wire antenna for 80 meters. I have two 85'
>> towers that support a nearly-square80 meter full-wave loop broadside
>> to
> EU.
>> It fits nicely, but the bottom is only about 10' off the ground.
>> It's fed in the center of one vertical sidewith a 1/4 wave of RG/11.
>> It works
> well.
>> I'd like to hear of opinions or experience with adding awire
>> parasitic element at this low height. Specifically, I'd like to add
>> a half-wave wire yagi element spaced about .15WL that would be
>> switchableto 3 different
>> lengths: phone director, CW reflector or phone ref/CW dir. I change
>> the physical size of the loop for CWor phone. I'd like to remotely
>> switchdirection (and mode) of the resulting antenna by changing the
>> length of theyagi element.
>> Any opinion as to the usefulness of a parasitic element ofthis design
>> with the whole thing so near ground? The yagi element will probably
>> only be about30' in the air. I don't expect 2 elementperformance,
>> but I don't want to bother if someone already knows it would be
>> awaste of
> time.
>> 73
>> Dick
>> N4RA
>>
>>
>>
>>
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>>
>>
>>
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