[TowerTalk] Inverted L Tuning Question

[RICHARD SOLOMON]

Is that article available on line ?
 
Thanks, Dick, W1KSZ> Date: Thu, 4 Dec 2008 18:22:55 -0800> From: n6ki73 at gmail.com> To: w7why at verizon.net> CC: towertalk at contesting.com> Subject: Re: [TowerTalk] Inverted L Tuning Question> > The issue with teh AM BC Strong Signal interference is addressed in> the Nov/DEC NCJ> ( National Contest Journal ) magazine article> ..and article uses exact same antenna analyzer as Dick is using !> 73, Dennsi N6KI> > On Thu, Dec 4, 2008 at 6:09 PM, Tom Osborne <w7why at verizon.net> wrote:> > > Hi Dick> >> > You can get some screwy readings if there is a BC station nearby. I can't> > even use my analyzer here on my 160 inverted L because of RF from the> > local.> > I have to use the SWR bridge in the shack. 73> > Tom W7WHy> >> >> >> > > Hi Guys,> > >> > > I'm trying to set up a 160-m. Inverted L for ARRL-160 this weekend but am> > > having an interesting tuning problem. All thoughts appreciated!> > >> > > The Inverted L is made up of #12 stranded copper wire 136' in total> > > length:> > > 82' vertical and 54' horizontal. The vertical wire is spaced 6' from a> > > 88'> > > self-supporting tower with a Cushcraft XM-240 mounted on top. (XM-240> > > elements> > > are not grounded) Initial radial system is 2- 135' radials laying on> > > the> > > ground- not much but two similar radials worked pretty well on my 60'> > > tower last> > > year as the towers are 150' from a salt water river.> > >> > > Placing the Antenna Analyzer (AIM 4170) at the base of the Inverted L> > gets> > > the following measurements:> > >> > > 1) With the coax braid connected to the tower base which has two 8'> > ground> > > rods: lowest SWR is 3.9 at 1.776 Mhz and Z = 79.> > >> > > 2) With coax braid only connected to the two radials (and not the tower> > > base): lowest SWR is 1.62 at 1.614 Mhz and Z = 81.> > >> > > It was my understanding that the coax braid should be connected to both> > > the> > > radials and the base of the towers gnd system, but as you can see the the> > > minimum SWR and resonant freq. go crazy when I do.> > >> > > Any recommendations what I can do to get it working before tmw night?> > >> > > 73,> > > Dick- K9OM> >> > _______________________________________________> >> >> >> > _______________________________________________> > TowerTalk mailing list> > TowerTalk at contesting.com> > http://lists.contesting.com/mailman/listinfo/towertalk> >> _______________________________________________> > > > _______________________________________________> TowerTalk mailing list> TowerTalk at contesting.com> http://lists.contesting.com/mailman/listinfo/towertalk