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Old October 22nd 09, 02:21 AM posted to rec.radio.amateur.antenna
David Thompson David  Thompson is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 81
Default Antenna Pattern: Carolina Windom

I have a Carolina Short 80 formerly called the Carolina 80 Beam up. Its been
up since about 1990 and is a good performer.

On 80 it does good off the ends but has a skewed figure 8. My antenna is
broadside N and S. K4UEE told me that from the Juan Fernandez operation a
few years back I was about the loudest on 75 SSB. I regularly worked EM1
from near the South pole with 9+ both ways. On 20 the pattern is still a
figure 8 but with a big lobe off the ends so I worked VK and ZL from Georgia
one year in the Oceania Contest.

I have two vertical short dipoles on 75 and 80 and another Carolina Short 80
broadside say NE/SW would probably do as good. To be really effective you
have to get it up at lesat 50 feet and higher is better!

My version of the Short 80 is only 84 feet horizontal.
I have the three vertical sections with the one at the feedpoint radiating.
The DMU matching 52 ohm coax to the 300 ohm point. The DMU also lets the
shield radiate. The 22 foot piece of coax teminates in a Line Isolator
balun to cut the radiation to the shack at that point.

Just wish Radio Works would fully explain the antenna. It is very difficult
to model but thanks to Dr. Dave then W0MHS (now W7FB) he ran it on his
mainframe modeling program. We never got NEC to show us anything beyond a
OCF windom model.

Dave K4JRB