Dear Reg:
Quite. I have found it more useful to use frequency.
73 Mac N8TT

P.S. The peaks and nulls suggested by the equation agree quite well when
compared to those resulting from using a "perfect" ground with EZNEC/4 as
long as the angles are less than about 30 degrees. In FS, the Yagi is down
1 db at 21.5 degrees and down 2 db at just under 30 degrees.

--
J. Mc Laughlin; Michigan U.S.A.
Home:
"Reg Edwards" wrote in message
...
If one writes the equation, for elevation angles of nulls and maximums, in
terms of free-space wavelength instead of frequency, an even more simple
equation is obtained :

Beta = ArcSin( N * Lambda / 4 / Height ) degrees.

Where Lambda is free-space wavelength
and Height is height above ground.

When N is odd, Beta corresponds to a maximum in the pattern.
When N is even, Beta correspnds to a null in the pattern.
----
Reg, G4FGQ