On Sat, 22 Sep 2001 Pete Smith <n4zr@contesting.com> writes:
>
> At 12:41 PM 9/22/01 -0400, Dave, AA6YQ wrote:
> I probably should have made this point earlier, but working to this
> level of precision is pointless for HF antennas, typically with 1/2
power
> beamwidths of 30 degrees or more. That's why I hoped we could avoid
> resurrecting the True North thread again.
>
Actually, the - 3dB beamwidth of a 5L Yagi on a .75WL
boom is closer to 50+ degrees. The beamwidth of a
3L Yagi is closer to 60 degrees.
Another interesting observation is that the signal level
at +/- 45 degrees is roughly equal to that of a dipole
for 2 to 5 element Yagi's. The 3 dB beamwidth's are
less for more gain, but the absolute levels at +/- 45 degrees
appear to be about the same (+/- a dB).
Tom N4KG
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