Brad,
Sounds like you have a good set up , how far off the ground is the bottom
wire? I just put up a 80 meter loop at the cottage and the bottom is
approx. 30` above ground (tall trees), I do`not have any feed line to it yet
but looking forward to this winter!! How long of a run do you have for the
coax , I am debating whether to use coax or open line as the run will be
about 250`. Any suggestions ?
73` Kevin VE3KKM
----- Original Message -----
From: "N9EN@VOYAGER.NET" <n9en@voyager.net>
To: <TOWERTALK@contesting.com>
Sent: Sunday, September 09, 2001 2:17 PM
Subject: Re: [TowerTalk] Delta Loop Polarization
>
> I currently use separate full-size delta loops for 80 & 160
> meters. Both of mine are supported at the top (apex) by
> a tower. Each of my loops is fed in one of the lower cor-
> ners with a length of 75 ohm coax, as a matching section,
> to get the impedance converted to 50 ohms.
>
> I used an article in QST from many years ago as a guide
> in setting up my loops. I don't know off-hand which
> issue it was but if anyone would like to know, I could
> find out for them.
>
> I don't know "exactly" how my loops are "polarized,"
> but I DO KNOW THAT THEY WORK...on 80 me-
> ters, I have somewhere around 267 wkd / 264 cfmd
> and on 160 meters, I have 165 wkd / 163 cfmd. I
> don't know how much better they might work if I was
> to feed them part-way up from one of the corners as is
> suggested in ON4UN's (and others') book, but they
> seem to work very well for me.
>
> 73 es gud DX de Brad, N9EN @ Radio Free Roscoe (IL)
> ----- Original Message -----
> From: <n4kg@juno.com>
> To: <TOWERTALK@contesting.com>; <ve9aa@nbnet.nb.ca>
> Sent: Sunday, September 09, 2001 7:16 AM
> Subject: Re: [TowerTalk] Delta Loop Polarization
>
>
> >
> > On Sat, 8 Sep 2001 "Mike & Coreen Smith" <ve9aa@nbnet.nb.ca> writes:
> > > Hi Tom (et al)
> > >
> > > Always enjoy reading your posts.
> > >
> > > My Delta loop as I recall is Vertically polarized. I fed it partway
> > > (I think 1/8WL(?)--been 9 years since I crawled into the thick trees
> > and
> > > installed> it) along the bottom edge.
> >
> > Vertical polarization of a Delta Loop results when you feed it
> > 1/4 WL down from the apex on one SIDE. Each side is .33 WL.
> >
> > Horizontal polarization of a Delta Loop results when you feed it
> > at the Apex OR in the middle of the Bottom Wire.
> >
> > Offsetting the feedpoint from either of these configurations results
> > in both horizontal and vertical components.
> >
> > Feed impedance is typically around 100-120 ohms and can
> > be matched to 50 ohms through a 1/4 WL (electrical) length
> > of 75 ohm coax such as RG-59.
> >
> > Tom N4KG
> > ________________________________________________________________
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> >
> > List Sponsored by AN Wireless: AN Wireless handles Rohn tower systems,
> > Trylon Titan towers, coax, hardline and more. Also check out our self
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> >
> > -----
> > FAQ on WWW: http://www.contesting.com/FAQ/towertalk
> > Submissions: towertalk@contesting.com
> > Administrative requests: towertalk-REQUEST@contesting.com
> > Problems: owner-towertalk@contesting.com
> >
> >
>
>
>
> List Sponsored by AN Wireless: AN Wireless handles Rohn tower systems,
> Trylon Titan towers, coax, hardline and more. Also check out our self
> supporting towers up to 96 feet for under $1500!!
http://www.anwireless.com
>
> -----
> FAQ on WWW: http://www.contesting.com/FAQ/towertalk
> Submissions: towertalk@contesting.com
> Administrative requests: towertalk-REQUEST@contesting.com
> Problems: owner-towertalk@contesting.com
>
>
>
List Sponsored by AN Wireless: AN Wireless handles Rohn tower systems,
Trylon Titan towers, coax, hardline and more. Also check out our self
supporting towers up to 96 feet for under $1500!! http://www.anwireless.com
-----
FAQ on WWW: http://www.contesting.com/FAQ/towertalk
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
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