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[TowerTalk] Compromise Vertical antenna ground system?

 To: [TowerTalk] Compromise Vertical antenna ground system? on4kj@skynet.be (on4kj) Sun, 29 Sep 2002 15:17:57 -0000
 ```----- Original Message ----- From: "j.a.hermans" To: ; Sent: Sunday, September 29, 2002 2:57 PM Subject: Re: Re: [TowerTalk] Compromise Vertical antenna ground system? > Hello all, > > What about using old coax to realize radials ? And let the velocity factor > shorten the radials.......... Maybe some cablemakers could produce cables > with velocity factors worst then the 0.68 ........... Dont know if going > down to 0.50 and less would be physicaly possible. > Heard about this somewhere a couple of years ago, but my remeberer has a > very low velocity factor ( 68 year young ). What can be proved by the > mathematic prof's ?....... > > 73's Jos on4kj > ----- Original Message ----- > From: > To: > Sent: Sunday, September 29, 2002 3:32 AM > Subject: Fw: Re: [TowerTalk] Compromise Vertical antenna ground system? > > > > Here is what W8JI had to say on the subject 2 years ago. > > > > Tom N4KG > > > > --------- Forwarded message ---------- > > From: "Tom Rauch" > > To: towertalk@contesting.com, "Avila, Edward" To: > > Date: Mon, 21 Aug 2000 20:48:49 -0400 > > Subject: Re: [TowerTalk] Compromise Vertical antenna ground system? > > > > > > > Well, my problem/question: I have very little room to run horizontal > > > radials from the base of a Butternut HF2V I'm thinking of installing on > > > the ground.....at the most 10-15' in some directions, which is a little > > > shy of 1/4 for 80 meters! Any suggestions for a compromises ground > > system > > > that will make the best of what I have to work with? Would more ground > > > rods help? More radials, even though they will be electrically short? > > > > There are always points of limited return in any design. Radials are > > no exception. > > > > The optimum number of radials for any radial length occurs when > > the open end of the radials is .025 to .05 wl apart. You should do > > this on the highest band you are seriously interested in. > > > > The point of diminishing returns for radial length is when the radials > > are about .2 wl long on the lowest band you are interested in. > > > > So if you are interested in 40 and 80 meters, the open ends of the > > radials should be no more than 3- 1/2 feet apart and the radials > > need be no longer than about 55 feet long. > > > > Wrapping a radial around to add length generally does nothing > > worthwhile. > > > > So in the short directions you need fewer radials than in the long > > direction. > > > > What I do is make a measuring line between two stakes. I then > > "leap frog" the stakes around the perimeter as I pull radials from > > the center point to each stake. > > > > A ground screen will generally only help when you have less than > > 30 or so radials. With more than 30 or so radials, a ground screen > > is a waste of time. > > > > A ground mounted vertical with a fair radial system is almost > > always much better than a "no ground" vertical...especially on 80 > > and 40 meters. > > > > > > 73, Tom W8JI > > w8ji@contesting.com > > > > > > > > ________________________________________________________________ > > GET INTERNET ACCESS FROM JUNO! > > Juno offers FREE or PREMIUM Internet access for less! > > Join Juno today! For your FREE software, visit: > > http://dl.www.juno.com/get/web/. > > _______________________________________________ > > AN Wireless Self Supporting Towers at discounted prices, > > See http://www.mscomputer.com > > > > Wireless Weather Stations now \$349.95. Call Toll Free, > > 888-333-9041 for additional information. > > _______________________________________________ > > Towertalk mailing list > > Towertalk@contesting.com > > http://lists.contesting.com/mailman/listinfo/towertalk > > > ```
 Current Thread Fw: Re: [TowerTalk] Compromise Vertical antenna ground system?, n4kg@juno.com [TowerTalk] Compromise Vertical antenna ground system?, on4kj <= [TowerTalk] Compromise Vertical antenna ground system?, Paul Playford