Dick,
Thanks for sharing your observations on your 40M four-square vs. a
40-2CD. My only caveat is to keep in mind that the comparison you make
during the summer will not always jibe with the same comparison in
winter. Radiation angles tend to be higher in the summer which would favor
the low yagi over the verticals. Your observation about the gain of a
four-square being 6 dB *over a vertical* which makes it about even with a
dipole over ground is absolutely correct. However, its not the entire story.
We've been using a wire four-square on 80M here at K8CC since 1994. We've
had just about every kind of 80M DX antenna here at this location: slopers,
delta loops, bobtails, half-squares, a 3L wire yagi and even a beautiful
N4ZC-style log periodic with the center at 110' and the ends at 90'. It's
my opinion (and shared by my guest operators) that none of these antennas
match the four-square, at least on 80M when you're limited to 120' supports.
That is not to say that the others were bad antennas. The simple little
half-square made UN2L's "loud LP 80M signals" list one year. The wire yagi
and N4ZC log periodic made lots of gain and were great pileup
crashers. But until we put up the four-square we couldn't hear down to the
weak layer of EU necessary to be able to run successfully on CW from
W8. Once we put up the four-square, the results were immediately noticable
on our 80M line score, and our 80M op was a lot happier too.
Again, I agree with your observation that verticals (and hence,
four-squares) don't radiate as much signal as a dipole over ground. I've
often found, particularly on 75 SSB that with the four-square we can hear
more DX stations than we can work. With northern Europeans particularly,
I'll call and call a perfectly copiable SM or OH and not even get a QRZ?
from them. My gut says if I could run about four or five KW output the
transmit signal from the four-square would match the ability to
receive. However, my conscience won't let me do that...
A couple of years ago K3LR (who has a great 80M four-square made from
Hy-Towers) decided to try some big horizontal antennas like a W2PV 2L quad
and a 3L linear-loaded yagi. Perhaps he'd like to share his observations
here on the reflector, but neither antenna replaced his four-square.
Finally, the answer for 80M might be different than for 40M...
73,
Dave/K8CC
>From Harri M. Mantila OH6YF" <harry@oh6yf.com Wed Jul 10 03:31:13 2002
From: Harri M. Mantila OH6YF" <harry@oh6yf.com (Harri M. Mantila OH6YF)
Subject: [CQ-Contest] WRTC guests are already in Finland! Photos...
References: <200207091646.g69GkoV02066@localhost.localdomain>
Message-ID: <000e01c227b9$dcc20110$0100a8c0@oh6yf1>
Hi!
I have put some more photos to my WRTC photo gallery at:
http://wrtc.oh6yf.com
73 de Harry OH6YF
________________________________
Harri M. Mantila
OH6YF-OH0MYF
Tel: +358505472478
harry@oh6yf.com
http://www.oh6yf.com
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