I am just finishing up my first season with the K9AY loop - no other
directional antennas on the low bands. I erected two loops at right
angles, and use a Vactrol device to vary the termination resistance. I
get the best results on 80 meters, where the S/N ratio is improved over
my vertical on all DX stations. I can get clear copy on signals I can
just barely hear on the vertical or inverted L. The reduction in QRN
from distant storms was very dramatic, with the crashes many S units
down compared to the other antennas (again, best on 80 meters). 160
performance is not as good - no improvement noted in S/N ratio. On the
AM BC band, the front to back ratio varies all over the place, with up
to 7 S unit difference on weak signals during the daytime. Nighttime
generally shows 2-3 S units difference F to B. I note that the Vactrol
setting for best F/B ratio is different for BC, 160, 80, 40, as
advertised. With the Vactrols going for something like $2.50, it's
probably the cheapest and most effective means of varying the
terminating resistance.
Larry Molitor wrote:
...snip...
>
> I would be interested in hearing about others experiences with the RX
> antennas I've reported on. With all the possible variations in construction
> and installation, a single users data is not always significant. Taken
> together, many different inputs can be very valuable.
>
> 73,
>
> Larry - W7IUV
>
--
K8AC
Floyd Sense - Angier, NC
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