K6UJ:
> Has anyone used the HFTA program and can tell me the best height
for a 15 meter
yagi for 6000 miles.
Your question depends on many variables. There are two
programs that you
can use to help answer your question yourself:
1. What angle is optimum? Depends on stage of the Solar Cycle, time of day,
short vs long path, etc. HamCAP (friendly front end for VOACAP) can
answer this:
http://dxatlas.com/HamCap/ (e.g. 8 degrees from 16-17z short path
from W6 to DL)
2. How do I optimize my antenna height for those angles? HFTA is the answer
which you already have in the book. Here's an example from my QTH to EU:
http://users.vnet.net/btippett/terrain_&_toas.htm (NB angles in
purple in 2nd plot)
Optimum angles can vary greatly from the beginning to end of
the opening.
To EU I often find low angles best at the beginning and high angles
best at the
end, but that might not hold true for CA to EU.
73, Bill W4ZV
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