K9YC wrote: "But there IS a difference in efficiency that looking ONLY at the
pattern misses."
Your point is unclear to me. Of course the pattern of a horizontal antenna
changes with changing height and with other environmental factors. If the
antenna is actually on the ground the efficiency is pretty terrible, but it
does not have to be very high before efficiency does not change meaningfully
with height - assuming that total radiation is considered rather than just that
which is useful.
However, I was only describing a horizontal dipole at around 5/8 wavelength
high. NR1DX suggested that because the ends are lower than the centre that
there was now an additional "significant vertical component". There is not if
the included angle is shallow, which in my case it is.*
73 Roger
VE3ZI
*(I stated that the ends were at 250' - they are at least that, and could be up
to about 290' - but I have not accurately measured the tension in the support
rope nor allowed for stretch so I cannot be specific about the catenary.)
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