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Re: Topband: advice on simple end fire array

To: Matt Murphy <matt@nq6n.com>
Subject: Re: Topband: advice on simple end fire array
From: Tim Shoppa <tshoppa@gmail.com>
Date: Mon, 5 Dec 2016 13:30:20 -0500
List-post: <topband@contesting.com">mailto:topband@contesting.com>
I looked at my past logs for patterns, and I might hazard a guess that
holding the Stew nearly a week before Christmas, will enhance EU numbers
compared to some recent years where it was run between Christmas and New
Years and EU turnout seemed unusually low. Just my guess!

My previous attempt at phasing was done with a length of RG-6 that was in
the shack and swapped between elements with relays. Lots of alligator clips
were in my past temporary setup! The spacing between two loops was about
1/4 wavelength which seems very short by Gary's standards but that's all I
had room for.

This seems to be the standard reference on phased K9AY's, by Gary himself:
http://www.aytechnologies.com/TechData/K9AYLoopArrays.pdf

As you set things up, keep in mind the very nice usability of W1AW code
practice and bulletin signals on weekdays at 1802kc.

Tim N3QE

On Mon, Dec 5, 2016 at 1:12 PM, Matt Murphy <matt@nq6n.com> wrote:

> Tim, that sounds like good advice.  I had been thinking that the end-fire
> array would offer a chance for me to dig into some of the math and low-end
> test equipment creating the transformers, but I think your broader point
> that being able to improve SNR at a range of azimuths is likely far more
> beneficial in the Stew than simply focusing on EU.
>
> Could you describe how you had your two arrays phased and what improvement
> you initially noticed (when you had the array in place) over a single
> array?
>
> 73,
> Matt NQ6N
>
> On Mon, Dec 5, 2016 at 11:45 AM, Tim Shoppa <tshoppa@gmail.com> wrote:
>
>> From where I am in W3, the EU numbers in a Stew (including prestew and
>> summer stew) seems highly variable. Many "good non contest nights" I work
>> more EU than in a stew.
>>
>> I would put reversibility high on your list because you could potentially
>> pick up more points from LP or QRP stations to the west, than from EU.
>>
>> I myself hope to get my array of Two phased K9AYs back together.
>>
>> Tim N3QE
>>
>> Sent from my iPhone
>>
>> > On Dec 5, 2016, at 12:26 PM, Matt Murphy <matt@nq6n.com> wrote:
>> >
>> > In preparation for the Stew I'm going to attempt to put up a small end
>> fire
>> > array aimed at EU on my small suburban lot.  There are a large number of
>> > books and articles about this topic, but my short-term goal is to build
>> > something simple that I can improve upon over the winter as time allows.
>> >
>> > I do not need the array to be switchable, since most of the points I'm
>> > likely to get would come from EU.
>> >
>> > I was thinking about creating three short verticals along the lines of
>> the
>> > YCCC receive array (with active coupling) or using the W8JI recommended
>> > method with passive components.
>> >
>> > What approach to phasing makes the most sense given my simple
>> requirements?
>> >  Advice on spacing?  What's the recommended approach to modeling a
>> system
>> > like this to test subtle variations in phasing and spacing?
>> >
>> > 73,
>> > Matt NQ6N
>> > _________________
>> > Topband Reflector Archives - http://www.contesting.com/_topband
>>
>
>
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