Patrick is correct. the balun at the top of the feedline is called a DMU in my
Carolina 80 Neam (also called the Carolina Short 80). At the end of the 21 foot
coax is a Line Isolator that cuts the RF at that point. The Calolina OCF's
don't work right if the balan at the top cuts the RF at that point.
I have had great luck with My Carolina Beam or short 80. Mine is only 84 feet
long with 21 feet vertical at the short end and 32 feet vertical at the long
end. I found that there is substantial radiation off the long end on 80 and
20. Several years ago I worked the VK/ZL Oceania Contest as my KT-34XA was
down for repair and made 40 Qsos on 20. However, the main pattern is slightly
off center broadside. I have worked the VP8 Islands with great success. I
easily worked the 3Y Dxpedition a few years ago and I worked the Juan Fernandez
Island a few months ago barefoot in a pile up.
73 Dave K4JRB
-----Original Message-----
>From: Patrick Greenlee <patrick_g@windstream.net>
>Sent: Jan 24, 2015 4:23 PM
>To: towertalk@contesting.com
>Subject: Re: [TowerTalk] Carolina Winsome and vertical radiator question
>
>No insult intended, Bill, I just want to mention something important and
>if you don't know it could bite you. Of the two baluns, the upper one
>between your approximate 90 ft wire and your approximate 180 ft wire,
>has to be one that does not eliminate common mode currents flowing on
>the outside surface of the 22 ft coax. OOPS, your 21 ft coax (mine is
>22ft.)
>
>That common mode current provides the radiation needed from that
>vertical 21 feet of coax. I cant quote mfg and part number but you do
>want to use the correct type balun. Baluns that prohibit/attenuate
>common mode current on the outer surface of the coax are terrific for
>their intended purpose and I use them but NOT between the unequal legs
>of a Carolina Windom. The vertical 21 feet of coax is a part of the
>antenna N O T part of the feedline. The feed point is at the lower of
>the two baluns.
>
>Usually my OCF dipole does about as good as my Hy-Gain Hy-Tower for 10%
>of the cost or less except on 10M where my tuner can't make a go of it.
>
>Good luck, Bill, hope to hear you on that OCF dipole.
>
>Patrick NJ5G
>
>
>On 1/23/2015 11:33 PM, Bill Bennett wrote:
>> I have noticed that the CW160 and CW80 have the same 21 foot vertical
>> radiator between baling and choke. Why 21 feet?
>>
>> Reason I ask is I am trying to roll my own CW160. I noticed that Radio
>> Works uses RG58 with foam dielectric and I would like to use RG8. Do I need
>> to account for velocity factor difference?
>> Thanks
>> Bill Bennett K4IBC
>> _______________________________________________
>>
>>
>>
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>
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