If a significant part of the nighttime QRN/QRM is realy coming from the
east then a directional receiving antenna should be considered. Two small
loops spaced 1/8 wavelength (275m) and fed with 90 degrees phase difference
give a 15dB F/B ratio while having a rather wide opening angle (enough to
cover most of VE/W from Europe). This would bring eastbound QRM/QRN 2/3
s-points down.
Spacing could be reduced at expence of the F/B ratio (abt 5dB at 100m
spacing).
Some years ago I have written a small turbo pascal program that simulates
the radiation pattern of 2 loops or verticals (or combination of both).
Initial goal was to see if a small directional receiving antenna could be
made for 80/40m.
If there is some interest I will se if I can adapt it for longwave.
73, Rik ON7YD
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