John Smith wrote:

About 21 degrees. For calculation purposes, mentally move the antenna down 8
feet. So you now have a triangle with altitude of 26 feet and a hypotenuse
of 73 feet. The sine of the angle you want is 26/73 or .3562. The cosine of
.3562 is 20.86 degrees.

If you don't frequently use what you have learned, it evaporates. . .

True enough -- "cosine" above should be "arcsin". The arcsin of a number
is the inverse sine, or the angle whose sine is the number. Cosine is a
different trigonometric function, defined by a ratio of different sides
than the sine.

Roy Lewallen, W7EL