The arrival angle data for HFTA (and VOACAP) are limited to 30 MHz max.
However HFTA's ray tracing seems valid at 6M (for 2M I suspect the spacing
interval of the radial plots would need to be decreased). So at least you
could see how antenna height interacts with surrounding terrain in critical
directions.
If you want the radial elevation plots for your location (needed to use
HFTA), send me your latitude and longitude in decimal degrees to at least
four places (DDD.dddd with N, S, E W) and I will e-mail you a zip file with
the radials plots, if you don't want to learn to use MicroDem to generate
them yourself. If its for 6M use I could decrease the sampling interval to
half the distance used for lower bands.
For 2M coverage it is probably better to use Radio Mobile with 1/3 arc
second DEM's of your terrain, although that's not so useful for DX coverage.
Steve, W3AHL
I don't know if HFTA has any arrival angle data for 6M. It's
predecessor YTAD did not.
Without arrival angle data how would you know some antenna height change
is good, bad or indifferent.
I seem to recall Es prop (at least for 1 hop) is relatively high angle.
If this is what one is after, then lowering rather than raising the
antenna is a better idea. Many 6M ops find 20-25' works pretty well.
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