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Re: Topband: Wellbrook receive loop performance

To: Top Band <topband@contesting.com>
Subject: Re: Topband: Wellbrook receive loop performance
From: joe <galicic@comcast.net>
Reply-to: galicic@comcast.net
Date: Tue, 10 Apr 2012 11:04:33 -0400
List-post: <topband@contesting.com">mailto:topband@contesting.com>
I built it in one evening using two pieces of scrap 1x3 lumber for
spreaders. I pounded in four large wire staples to hold the wire to the
spreaders and threaded both loops through them. The five wire and one
wire pickup loop are not separated.  I used a variable cap of roughly
150-200PF to resonate the 5 wire loop.  I fed the pickup loop directly
with RG-58 coax.  No matching transformer. The loop is roughly 32 inches
square.  I tune the cap for maximum noise for the desired frequency.
The loop is tunable from about 1600 - 1850 KHZ. 

I modeled my loop after the following designs for unshielded loops.

http://www.i1wqrlinkradio.com/antype/ch9/chiave1183.htm

http://members.verizon.net/~vze24qhw/loop.html


On Tue, 2012-04-10 at 08:49 -0400, joe wrote:
> I am experimenting with a small one meter square loop.  It is 5 turns of
> #14 wire with a one turn pickup loop.  Feeding the pickup loop directly
> with 50 ohm coax.  Using air variable cap to resonate the 5 turn loop.
> I have it setup in my basement on a tripod with small TV rotator and it
> works amazingly well.  I can null stations about 3-4 S units with it and
> it is about 4 S units (24 DB) quieter than my inverted L.  I also have a
> short 140 foot BOG and the loop performs nearly the same with the added
> ability null out noise sources.  I plan to move it outside and take some
> more measurements.  I'm pretty impressed so far.  -Joe KB3KJS
> 
> 
> 
> 
> On Mon, 2012-04-09 at 17:17 -0700, Jim WA9YSD wrote:
> > How well does this antenna perform in a City environment like mine on top 
> > of a 50 foot tower?
> >  
> > Stay on course, fight a good fight, and keep the faith. Jim K9TF/WA9YSD
> > _______________________________________________
> > UR RST IS ... ... ..9 QSB QSB - hw? BK
> 
> 
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK


_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK

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