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References: [ +subject:/^(?:^\s*(re|sv|fwd|fw)[\[\]\d]*[:>-]+\s*)*Topband\:\s+More\s+\-\s+lightning\s+protection\s+on\s+4\s+sq\s*$/: 12 ]

Total 12 documents matching your query.

1. Topband: More - lightning protection on 4 sq (score: 1)
Author: "David Raymond" <daraymond@iowatelecom.net>
Date: Tue, 10 Jun 2008 21:43:22 -0500
Greetings everyone. . . I received several responses to my email regarding installation of lightning protection on my 160 meter four square. Several people suggested I put a Polyphaser on the coax ou
/archives//html/Topband/2008-06/msg00007.html (7,699 bytes)

2. Re: Topband: More - lightning protection on 4 sq (score: 1)
Author: "Harold Smith" <w0rihps@sbcglobal.net>
Date: Wed, 11 Jun 2008 13:21:42 -0500
Dave, The Polyphaser lightning arrestors are not just a capacitor. It is not a big capacitor. On the antenna side is a gas discharge tube to ground and it has a series capacitor to the equipment. Th
/archives//html/Topband/2008-06/msg00008.html (9,188 bytes)

3. Re: Topband: More - lightning protection on 4 sq (score: 1)
Author: Rick Stealey <rstealey@hotmail.com>
Date: Thu, 12 Jun 2008 21:26:48 +0000
According to my calculations at 2 MHz: If the capacitor in series with the line inside the Polyphasor was .01 uf it would have a reactance of 8 ohms and the phase shift would be 9.15 degrees. If it w
/archives//html/Topband/2008-06/msg00009.html (7,581 bytes)

4. Re: Topband: More - lightning protection on 4 sq (score: 1)
Author: "Harold Smith" <w0rihps@sbcglobal.net>
Date: Fri, 13 Jun 2008 09:18:06 -0500
Hello Rick: I opened a Polyphaser IS-50UX-C0 and it had 2 small disk ceramic capacitors in parallel. I couldn't read the values by sight so I measured the value. It was 0.02 mfd. So each capacitor w
/archives//html/Topband/2008-06/msg00010.html (8,189 bytes)

5. Re: Topband: More - lightning protection on 4 sq (score: 1)
Author: Roger D Johnson <n1rj@roadrunner.com>
Date: Fri, 13 Jun 2008 17:29:11 -0400
I did a quick EZNEC model and adding -4 Ohms reactance (.02 ufd)at the feedpoint of the verticals showed no change in F/B ratio. I would also add a robust spark gap and an RF choke to act as a static
/archives//html/Topband/2008-06/msg00011.html (9,675 bytes)

6. Re: Topband: More - lightning protection on 4 sq (score: 1)
Author: Rick Stealey <rstealey@hotmail.com>
Date: Fri, 13 Jun 2008 23:13:52 +0000
Ok we have agreement all around. Thanks Price for the data. Now we know we have .02 in series with 50 ohms, so that is about 4 ohms of reactance and 4 ohms in series with 50 ohms results in a phase s
/archives//html/Topband/2008-06/msg00012.html (8,322 bytes)

7. Re: Topband: More - lightning protection on 4 sq (score: 1)
Author: Roger D Johnson <n1rj@roadrunner.com>
Date: Fri, 13 Jun 2008 21:37:06 -0400
Don't forget that it's the relative phase between the elements that determines the pattern. Adding a small reactance to the feedpoint of each element should not change the relative phase between the
/archives//html/Topband/2008-06/msg00013.html (9,626 bytes)

8. Topband: More - lightning protection on 4 sq (score: 1)
Author: "Lee K7TJR" <k7tjr@msn.com>
Date: Fri, 13 Jun 2008 19:43:34 -0700
Adding 5 ohms reactance to the 160 meter 4-square elements is just like tuning down frequency about 20kHz from a verticals resonance. They have about 5 ohms reactance of their own then. Adding the ar
/archives//html/Topband/2008-06/msg00015.html (7,073 bytes)

9. Re: Topband: More - lightning protection on 4 sq (score: 1)
Author: Ken Brown <ken.d.brown@hawaiiantel.net>
Date: Fri, 13 Jun 2008 17:27:53 -1000
Hi all, Sounds like you're on the right track to determine the possible effect of adding series capacitors on the relative phase and amplitudes of the currents in a four square array. The feed point
/archives//html/Topband/2008-06/msg00016.html (9,212 bytes)

10. Re: Topband: More - lightning protection on 4 sq (score: 1)
Author: "James Wolf" <jbwolf@comcast.net>
Date: Sat, 14 Jun 2008 18:36:49 -0400
The series capacitor exists in the Polyphaser box to allow static voltage to climb high enough to trigger the gas discharge tube if there is a DC ground in the receiver. Many receivers have an input
/archives//html/Topband/2008-06/msg00020.html (9,212 bytes)

11. Re: Topband: More - lightning protection on 4 sq (score: 1)
Author: "Harold Smith" <w0rihps@sbcglobal.net>
Date: Sun, 15 Jun 2008 10:01:25 -0500
Jim, The gas discharge tube is at the antenna input to ground. The capacitor has nothing to do with when the gas tube will fire. As I stated before, PolyPhaser has a very good handbook on lightning
/archives//html/Topband/2008-06/msg00025.html (9,895 bytes)

12. Re: Topband: More - lightning protection on 4 sq (score: 1)
Author: "David Raymond" <daraymond@iowatelecom.net>
Date: Sun, 15 Jun 2008 23:04:59 -0500
like tuning down frequency about 20kHz from a verticals resonance. They have about 5 ohms reactance of their own then. Adding the arrestors to each element is like moving the resonant frequency up ab
/archives//html/Topband/2008-06/msg00037.html (8,148 bytes)


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