I'll believe your test, but a better
test is a simple dipole against a simple
vertical. That way, implementation
problems of the 4-square and Yagi don't
confuse the results.
This must vary with location. At my QTH,
before building my 7 element vertical
array, I A/B'ed a simple vertical against
a 90 foot high inverted vee. Within the
resolution I could get switching back
and forth, these were interchangeable for
me. Maybe the dipole really is 2 dB better,
and I just can't measure to that resolution.
I haven't tried it, but wouldn't be surprised
if a dipole did start to get a substantial
advantage at a really high height, like 140+
feet.
From all the positive press than 90 foot
high beams on 40m get, I expected much
more than I got with my vee at 90 feet.
(Note: proper precautions were taken
to avoid mutual coupling effects between
antennas).
Rick Karlquist N6RK
richard@karlquist.com
www.n6rk.com
www.karlquist.com
> -----Original Message-----
> From: towertalk-admin@contesting.com
> [mailto:towertalk-admin@contesting.com]On Behalf Of Dick Green
> Sent: Monday, July 08, 2002 10:51 AM
> To: CONTEST; Tower; YCCC
> Subject: [Towertalk] 4-square vs 40-2CD
>
>
> And the winner is...
>
> I just had the rare opportunity to compare two very
> different 40m antennas
> "side-by-side" and thought the results would be of
> interest. I've had a 40m
> 4-square with 60 buried radials per element for about five
> years. Yesterday,
> I put a used 40-2CD at the top of a 50-foot AB-577/GRC
> portable guyed
> military surplus mast (HD-73 rotor) and compared the two
> antennas. There was
> no contest at all: even at 50ft, the 40-2CD is 1-2 S-units
> louder than the
> 4-square. Assuming my 1000MP meter is calibrated for 6dB
> per S-unit, that
> translates to 6-12dB. I'm sure getting the 40-2CD up higher
> would improve
> these results.
>
>
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