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#1
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The VERT1 vertical that comes with EZNEC is 1/4WL on 40m.
It will be 5/8WL on 17m. (7.2 * 2.5 = 18) EZNEC sez the feedpoint impedance on 17m will be about 100-j470 ohms. Hi Cecil, He was asking about 24MHZ which is 12 meters. EZNEC sez a 5/8 on 24MHZ is 63-j206, more or less. As others have pointed out a lot of factors will enter into the final installed impedance. Another matching method, for 63-j206, is feed the antenna with a 1.2 meter length of 300 ohm twinlead- 1:1 balun- 50 ohm coax. The twinlead transformer gives 43-j0. Don't tell Reg, but I did that on the Smith Chart in 48.32 seconds:-). 73 Gary N4AST |
#2
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JGBOYLES wrote:
Hi Cecil, He was asking about 24MHZ which is 12 meters. EZNEC sez a 5/8 on 24MHZ is 63-j206, more or less. I had forgotten I had changed VERT1 from tubing to #14 wire. That was the problem with the higher impedance. With 3 inch dia. vertical tubing the impedance on 18 MHz is 62-j190. -- Sorry & 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
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