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## Re: [TowerTalk] Phased verticals one direction

 To: Bob Ad5vj Re: [TowerTalk] Phased verticals one direction Terry Conboy Thu, 03 May 2012 10:17:51 -0700 mailto:towertalk@contesting.com>
 ```Bob, This is almost ok, but using 468/f is a typical length for a half-wave dipole including the shortening due to end effect (-5%). At 7.15 the wavelength is 983.571/7.15 = 137.56 feet. In your coax with VF=0.6779, this would be 93.25 feet. So a quarter wavelength line would be 0.25*93.25 = 23.31 feet and a three quarter wavelength line would be 0.75*92.25 = 69.94 feet. When I modeled this in EZNEC, with 3/4 wl line between the verticals and a 3/4 wl line to the Tx from vertical #1, the beam goes to the SW. With 5 ohms of ground loss, the gain is 2.56 dBi and the F/B is 8.8 dB. Feed Z is 86.2 - J 50.02 ohms or a 2.48:1 SWR at 7.15 MHz. Let me know if you need more info. 73, Terry N6RY On 2012-05-02 8:44 AM, Bob Ad5vj wrote: > My first Rodeo on phasing, need confirmation please. > > I am working on 2 34' phased verticals spaced 34' for 40 meters pointing in a > NE/SW line. > > SW ant we call #1 > NE ant we call #2 > > I am wanting ONLY NE direction. > > Using my MFJ-259B I have determined the length of coax I have (RG-11) to > measure 106.2' to the fault. > > Physically measuring the coax it comes to exactly 72'. > > Dividing 72/106.2 I get a measured velocity factor of .6779 according to the > MFJ manual. > > (468/7.150)/2 =32.7' per 1/4 wave > 32.7' X 3 = 98.1818 > for 3/4 wavelength > > 98.1818 X .6779 = 66.55' > > So this should be the physically measured coax length for the 3/4 wavelength > going to the #1 vertical. > > Then I do the same for a 3/4 coax wavelength from #1 to #2 antenna. > > > Does that sound right? > > 73, Bob AD5VJ > _______________________________________________ _______________________________________________ TowerTalk mailing list TowerTalk@contesting.com http://lists.contesting.com/mailman/listinfo/towertalk ```
 Current Thread [TowerTalk] Phased verticals one direction, Bob Ad5vj Re: [TowerTalk] Phased verticals one direction, Terry Conboy <= Re: [TowerTalk] Phased verticals one direction, john Re: [TowerTalk] Phased verticals one direction, W0MU Mike Fatchett Re: [TowerTalk] Phased verticals one direction, Rick Karlquist Re: [TowerTalk] Phased verticals one direction, john