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#11
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'Doc wrote in message ...
Paul, Another suggestion, end feed a center fed dipole. That doesn't make much sense, but thats because I don't know how to describe it. In effect, run the coax ~through~ one half of the dipole to the center where the feed point is. One way is to double the braid back onto it's self. The folded back braid makes up half the dipole, the center conductor is the 'other' half. I'm sure there are better descriptions and pictures somewhere, I'll see if I can find one. 'Doc Doc, I found some info on the antenna you describe. It can found at http://www.xs4all.nl/~pa0nhc/antenne/cobra80/cobra.htm And the weird thing is he had the exact same problem I'm having. I think this is the solution to my problem. Thanks Paul KC9EYE Hobart, IN |
#12
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It is called a coaxial antenna. It is usually used in the vertically
polarized orientation, but don't let that stop you from using it in any other orientation. "'Doc" wrote in message ... Paul, Another suggestion, end feed a center fed dipole. That doesn't make much sense, but thats because I don't know how to describe it. In effect, run the coax ~through~ one half of the dipole to the center where the feed point is. One way is to double the braid back onto it's self. The folded back braid makes up half the dipole, the center conductor is the 'other' half. I'm sure there are better descriptions and pictures somewhere, I'll see if I can find one. 'Doc |
#13
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"'Doc" wrote in message ... Paul, Another suggestion, end feed a center fed dipole. That doesn't make much sense, but thats because I don't know how to describe it. In effect, run the coax ~through~ one half of the dipole to the center where the feed point is. One way is to double the braid back onto it's self. The folded back braid makes up half the dipole, the center conductor is the 'other' half. I'm sure there are better descriptions and pictures somewhere, I'll see if I can find one. 'Doc That might be an original idea, a sleeve vertical mounted horizontally. Tam/WB2TT |
#14
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Paul, I've used one of these things when portable. Worked better than the mobile antenna, but I did use a tuner (wasn't all that worried about losses at the time, no harm to the tuner). To keep the weight/cost/bulk down I used RG-58 coax (it was going to be wound up and thrown in the trunk). If I were going to make it a 'permanent' (no such thing!) antenna I might use something larger, but I doubt it. The center 'feed point' was weather proofed by sealing it with some kind of 'goo', can't remember what it was, probably silicon. Also found that winding a 'choke' a few feet from the end where it came out of the folded back braid cut down on RFI problems. Not that they were 'bad', but it didn't hurt anything either. I wouldn't count on it ever being a 'DX antenna' (whatever that means), but it is an alternative... 'Doc |
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