My antenna is a pair of verticals spaced 1/4-wave with switchable
directivity. I can select either of two unidirectional patterns at 45
and 225 degrees (with the -3 dB points quite wide), and one bidirectional
pattern at 135/315 degrees.
Regarding Larry, W7IUV's question on skew paths, the 160m skew path case
I remember most is when I worked XZ (Myanmar) a few years ago. His
signal was markedly better on the unidirectional 225 degree pattern (out
of the south Pacific) rather than the bidirectional SE/NW pattern
(Myanmar is about 325 degrees from me on short path). This was quite
surprising to me at the time.
Skew paths to EU are quite noticeable and common on 40 meters (where I
have a rotatable Yagi). The usual skew is to the east and even ESE on
that band. The short path to central EU from here is about 30 degrees.
On 160m, on numerous occasions in late December (especially in 1997), I
have worked/heard Scandinavia at my sunrise, which one would think is the
long path to EU. However, the signals could not be heard except when I
was beaming short path to EU. Looking at a program such as GeoClock, it
could be readily seen that, at my sunrise, the sun had already set in
northern EU, therefore the path was in darkness all the way to that area
of the world on the short path. Strange that, when condx are good, EU
can be worked on short path at both sunset and sunrise around the
December solstice here in the western USA.
73, de Earl, K6SE
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