Dave,
Took me a while to get around to replying, but thanks for the observations.
If you read my IARU post, the 40-2CD performed very well under battle
conditions. Atmospheric noise was too high for S-meter comparisons, but I
felt louder on the 40-2CD and never got asked for a repeat. The 4-square was
a little less effective in that regard. The 40-square was a little quieter,
but I ended up using the 580' NE beverage when the noise got real bad. The
big surprise was that the 40-2CD was the same 5-15dB louder to VK2. Guess
the 4-square's angle advantage isn't worth 5.5 dB in the summertime. I'll be
checking that as we get into fall and winter.
I ended up using the 4-square almost exclusively for S&P on the second
radio. It's more than adequate for that purpose. You can't beat the instant
direction switching and deep F/B. It might be worth sweeping the band every
now and then with the 40-2CD to pick up real weak ones.
I modeled the 40-2CD at 50', 75', and 120', and that tells a pretty good
story as well. The gain is comparable, but the angle is 36 degrees at 50',
25 degrees at 75' and 15 degrees at 120'. I imagine that makes a heck of a
difference and will be raising the 40-2CD tower to 75 feet before the fall
contests. The F/B was somewhat better the higher you go, too, but nowhere
near the 4-square.
I really do think it's a different story on 80M and 160M. I've had excellent
results with the 80M 4-squares at K1RX and KT1V. For most of us, we just
can't get a yagi up high enough on those bands. The 4-square has a
tremendous advantage in that regard: as long as you've got the real estate,
can figure out how to raise 65-foot verticals (or top-loaded verticals), and
are willing to spend some time dealing with radials, then there's nothing
better. I use a delta loop at 75' on 80M and it beats the old inverted-vee
by a mile, but it's nowhere near as effective as a 4-square.
73, Dick WC1M
> -----Original Message-----
> From: David A. Pruett [mailto:k8cc@comcast.net]
> Sent: Tuesday, July 09, 2002 9:45 PM
> To: dick.green@valley.net; CONTEST
> Subject: Re: [CQ-Contest] 4-square vs 40-2CD
>
>
> 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
>
>
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