At 11:12 PM 01/06/00 +0100, Dan, S50U wrote:
>What other effect would a ground slope have on a radiation pattern of a
>vertical ?
In general, terrain which slopes downhill enhances radiation at very low
angles. This is true for both horizontal and vertical antennas. The
details depend on the antenna and the features of the terrain. K6STI's TA
(terrain analyzer) program can be used to model these effects for a
specific terrain profile. However, it is my experience that TA sometimes
produces rather strange results with some very large gain enhancements (10
to 20 dB more gain than flat terrain) at very low angles (below 10
degrees). I'm not convinced these results are accurate, but nonetheless
the trend is more gain at low angles compared to flat ground.
73, John W1FV
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