I made some signal to noise measurements last night between my short BOG
and LOOP. Local (100-300 miles away) cw signals. The Loop, which is
still living in my basement, is within 3DB of the BOG. I will move it
outside soon and see what happens to SNR. I still need to try it out on
some weaker DX stations.
The LOOP has also proved to be promising on hearing multiple AM
broadcast stations on the same frequency due to its good nulling
capability. I could never do this with the BOG or L.
On Tue, 2012-04-10 at 11:04 -0400, joe wrote:
> 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
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
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