Carol,
Not sure how much of a cluttered environment you live in, (suburb, farm
land, hill, beach, mountain, whatever)..but this does seem somewhat odd.
Why don't you do like I do after installing or just testing a new antenna?
I try to do 2 (or 3) things:
#1 - I place my antenna analyzer (aa-230pro) used as a signal source out
some distance from the antenna at a known beam heading
and rotate the antenna to give me a quick and dirty idea how clean the
pattern is.
That's pretty near field at a couple hundred feet, but it works.
#2 - I might get a local amateur (usually Dave, VE9CB about 15miles away) on
a known bearing to give me a carrier on the band of interest
and I rotate my antenna and make notes on a piece of paper. Also,
easy-peasy.
#3 - I don't usually need to do #3, but I have done it. Get the XYL to sit
in my HF mobile 1000-2000' away from the antenna and key my HF rig in the
car while I do as in #2
Sometimes I'll find that "xx band sloper just installed wherever" plays with
the patterns of several antennas. (Recently on 80m only, I notice my pattern
is skewed a little t the NW by a shed which has lots of metallic objects in
it, electrical wiring etc. and also some small antennas on it. Also we tend
to park 2 cars there next to it.
BTW, I sometimes see EU to the East (or even SE on backscatter) on 10-15 or
even 20m, but those are usually at known times and it's definitely not all
day, every day.
I think there's likely something in your near field playing with the
pattern. Like we say at work to end-user reporting a problem.."what did you
just do"?
It's all speculation until you do some measurements.
Mike VE9AA
Hello all,
In late summer, I had some minor work done on my towers and antennas. I used
a compass so that the beams were lined up correctly with N at 0 degrees and
NE at 45 degrees, EU direction. All monoband yagis have not loosened up,
but that EU now peaks at due East on all three yagis, separate towers, The
other directions behave properly; N to JA, W to the Pacific etc. Can anyone
explain why the change? There is about 15 db difference in signals from EU
at 90 degrees and EU at 45 degrees?
I understand that EU on 15m would be skewed at this point in the cycle, but
40m and 20m?
Carol
Mike, Coreen & Corey
Keswick Ridge, NB
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