All take-off angles are correct. All takeoff angles are incorrect, too. You
just need someone to hold all the other variables steady (like the height of
the d layer, etc, the atmospheric conditions, the sunspots, and a few other
variables----
Its a crapshoot. The right angle at noon may be wrong at sundown.


"Al Lorona" wrote in message
...
Hi, Everybody,

How does one determine the correct antenna takeoff angle to communicate
over
a certain distance?

I can't find any references anywhere that discuss this, taking into
account
all of the variables: height of ionosphere, frequency, etc.

Cecil Moore schreef:
Al Lorona wrote:
I can't find any references anywhere that discuss this, taking into account
all of the variables: height of ionosphere, frequency, etc.

The ARRL Antenna Book has charts and graphs of such.

And, for as far as I know, recent versions of the ARRL antenna book
include the HFTA program, to analyze the effect of sloping/unregular
terrain.

Arie.