AA5JG wrote: I was looking at a recent issue of CQ at the local
bookstore tonight (it wasn't the April issue) and in a column dealing
with semi stealth antennas, they mentioned that a 3/8 or 1/2 vertical
will show comparable performance to a 2 element yagi. Is this true?
In general, no. But it depends on the height of the Yagi. A Yagi on
the ground doesn't work very well. Also a 3/8 or 1/2 wave vertical won't
show any gain over a quarter wave vertical unless it has a much larger
radial system (although the take-off angle will be lower).
Considering the trade-offs, the rule for my station is vertical antennas
for 160, horizontal antennas for 40 and up. 80 meters is a crossover
point where either may be used.
HOWEVER, there is one thing I have been curious about for a while, and
that is the apparent superiority of a vertical to a horizontal antenna
on 160. Almost all the serious DXers on 160 use verticals, but those
that also have very high horizontal antennas report that they don't
compare well.
W8JI said: "I virtually never use the high dipole /(the 300ft one)/.
The 220 foot vertical or the 1/4 wave verticals beat it at almost any
distance, close or far. Only on very rare occasions is the 300 foot high
dipole equal or better at ANY distance. "
-end quote
This is not verifiable with EZNEC, but I do trust Tom's judgment at
evaluating antennas. EZNEC says the high dipole should be better at all
distances (in the dipoles best direction).
Also I was expecting that the 3 element 160 Yagi of OH0X to be louder
than it is. It doesn't seem much louder that the other OH stations. It
puts out a good signal but I'll bet a four square would give it a run
for the money (just a feeling). Of course EZNEC would not agree to
that. EZNEC shows the Yagi should win by a bunch of dBs.
160 is a strange band in many ways. This seems to be another one. Any
thoughts?
Jerry, K4SAV
John Geiger wrote:
> I have a question for the group about experiences with different antennas:
>
> I was looking at a recent issue of CQ at the local bookstore tonight (it
> wasn't the April issue) and in a column dealing with semi stealth antennas,
> they mentioned that a 3/8 or 1/2 vertical will show comparable performance to
> a 2 element yagi. Is this true? Will such a vertical really do as good as a
> 2 element beam?
>
> Also, how would a roof mounted 1/4 wave vertical compare to a 2 element
> tribander at a low height-like 25 feet or so?
>
> 73s John AA5JG
>
>
>
>
>
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