[Elecraft] {OT} - On the subject of "best" portable antennas

[Ron D'Eau Claire]

The pattern is the same no matter how an antenna is fed. In terms of height
vs pattern, here's a few reference points for height in wavelengths for a
horizontal radiator to better quantify the "higher is better" rule (at least
for working DX):

1/8 to 1/4 wave: About 6 dBi gain straight up. But it's a very broad lobe,
wider at 1/4 wave, which is why people work DX with such an antenna. The
gain is about 1 dBi at 20 degrees above the horizon. That's about the same
pattern as a 1/4 wave vertical over a good ground system. Bottom line, at
1/4 wave up, you can work DX with it although higher is better, for example:

1/2 wave: main lobe at 25-30 degrees about 8 dBi. It's fairly broad with
gains of about 3 dBi at about 10 and 50 degrees. 

1 wave: main lobe at 14 degrees, about 8 dbi, fairly narrow with a secondary
lobe nearly as strong at about 50 degrees

2 wave: lowest angle lobe at 7 degrees, about 8 dBi with multiple lobes at
about 25, 30 and 60 degrees.

73, Ron AC7AC

-----Original Message-----


N0AZZ wrote
> Another question what seems to be a minimum height for the Par to be 
> effective? Yes I know higher is better trying to get a handle on this 
> for an end fed. I have no experience with this type of antenna and 
> thinking of field use and supports.

Fred, in terms of angle of radiation versus height, it will behave similar
to a dipole.  If you can get it up a half wavelength or higher in the air,
great, but it will work well only a quarter wave off the ground (with higher
angle of radiation).  If the ground slopes down in the direction of
propagation, it doesn't have to be high at all.  I used it once on a
mountain summit about 6ft off the ground and it worked like gangbusters.

73,
Barry N1EU




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