Perhaps magnetic loop was an incorrect term - shielded-loop is better.
Yes - there are better low-band RX antennas. I also have a Hi-Z 3 element
vertical triangle array. It works, has directivity and decent rear rejection.
However, my triangle array has higher S/N than my shielded-loop.
My log book shows that on 160 and 80m my shielded-loop hears plenty of DX and
should not be dismissed as only being good for local RFI and QSOs. I don’t
rotate my loop - It does have a narrow null perpendicular to the plane of the
loop but the null is not noticeable in practical operation with proper loop
orientation.
For those who would like to improve their low-band S/N without the real estate
and/or $$ and effort to buy/build Beverages, BOGs, multi-element vertical
arrays, steerable loops, etc. a shielded-loop could make a noticeable
improvement in their low-band RX S/N.
73 Phil NA4M
> On Aug 7, 2018, at 4:58 PM, Mike Waters <mikewate@gmail.com> wrote:
>
> A loop such as that has a very narrow null at very low angles, and therefore
> it's usually not very effective for anything except for local RFI or another
> local ham. For power line or nearby QRN, it's useful. But that's about it.
> There are much better RX antennas.
>
> 73, Mike
> www.w0btu.com <http://www.w0btu.com/>
>
> On Mon, Aug 6, 2018, 7:37 PM Phil Duff <na4m@suddenlink.net
> <mailto:na4m@suddenlink.net>> wrote:
> > On Aug 6, 2018, at 7:06 PM, Cecil Acuff <chacuff@cableone.net
> > <mailto:chacuff@cableone.net>> wrote:
> > Wish I could find an effective RX antenna that showed a great s/n
> > improvement over the L.
>
> Look into a magnetic loop such as the design by N6RK as described in a past
> NCJ:
>
> http://www.n6rk.com/loopantennas/NCJ_loop_antenna_N6RK.pdf
> <http://www.n6rk.com/loopantennas/NCJ_loop_antenna_N6RK.pdf>
>
> I use one on 160/80 and find it effective at improving the S/N ratio over my
> vertically polarized 160m and 80m transmit antennas.
>
>
> de Phil NA4M
>
-. .- ….- --
Phil Duff na4m[at]suddenlink[dot]net
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