Tom,
sounds pretty reasonable for a second story system.I wonder if a "ground
tuner" like the one MFJ makes could help? of course they're intended for
unballanced antennas working against ground, but maybe such a tuner could
help make that long ground wire look shorter.
Tom Fowle
WA6IVG
On Tue, Aug 18, 2015 at 08:18:58AM -0400, Tom Behler wrote:
> Tom:
>
> At this point, my grounding system consists of one 8-foot ground rod that is
> connected to the main ground of the house electrical system with ten-gauge
> stranded copper ground wire. I then have a stranded copper ground wire
> running from the main ground connection up to the main ground lug on an MFJ
> window feed through panel in my shack, which is on the second floor of my
> house. All antennas are connected to that feed through panel. And, each
> piece of equipment (i.e. radio, amp, and tuner) are connected to the main
> ground lug on the feed through panel with 12-gauge copper ground wire. As
> far as I can tell, all ground connections are good.
>
> Tom Behler: KB8TYJ
>
>
> -----Original Message-----
> From: For blind ham radio operators [mailto:[log in to unmask]]
> On Behalf Of Tom Fowle
> Sent: Monday, August 17, 2015 10:58 PM
> To: [log in to unmask]
> Subject: Re: Question About Cobra Ultralite Senior Antenna
>
> Tom,
> first thoughts are about grounding.
> Though not familiar with the antenna, I assume it is basically a loaded
> dipole and that the manufacturer claims it's matchable on all bands.
>
> What is your R.F. grounding system like? is all the gear, particularly the
> xcvr, amp and tuner, well grounded together and to a good heavy lead to at
> least one ground rod?
>
> Tom Fowle WA6IVG
>
> On Mon, Aug 17, 2015 at 10:13:49AM -0400, Tom Behler wrote:
> > Hello, everyone.
> >
> >
> >
> > I guess this question is best directed to those who are familiar with
> > the Cobra Ultralite Senior antenna made by K1JEC, but I'll take
> > thoughts from anyone who is interested in replying.
> >
> >
> >
> > Several years ago, I purchased a Cobra Ultralite Senior antenna from
> > K1JEC, or Granite State Antenna in New Hampshire. My main reason for
> > making the purchase was to have operating capability on 80 and 160
> > meters. The antenna itself is up about 35 to 40 feet, and is strung
> > between trees on my property, and on a neighbor's property.
> >
> >
> >
> > The antenna works well on 80 meters, and much of 160 meters, when
> > tuned with my MFJ 998 auto-tuner.
> >
> >
> >
> > However, I have never been able to get it to tune on 40 meters. In
> > addition, the tuning and performance are questionable at best on 20,
> > 15, and
> > 10 meters. In fact, one problem I have noticed recently is that when
> > tuning it on 20 meters, using my MFJ998 auto-tuner and my ALS600, I
> > actually get RF coming through the PTT switch on my Heil gold line
> > mic. This, of course, is not good.
> >
> >
> >
> > All of this is prompting me to try to correct the situation.
> >
> >
> >
> > Several months ago, I contacted Joe at Granite State Antenna in New
> > Hampshire, and he suggested that I make sure the excess ladder line is
> > coiled in several loops, and is off the ground. I just double-checked
> > this, and it is what we did when we installed the antenna.
> >
> >
> >
> > A ham friend of mine has suggested that I cut off the excess
> > ladderline, and see if that helps.
> >
> >
> >
> > I am reluctant to do this, because the instructions say not to do so,
> > and it is one of those steps that will be difficult to reverse.
> >
> >
> >
> > I am thinking of purchasing some RF chokes to help with the issue,
> > bbut I still think there is a basic problem with my instalation.
> >
> >
> >
> > Fortunately, my Alpha Delta DXCC tunes well on40 through 10 meters,
> > but it would be nice if I could get the Cobra to do the same.
> >
> >
> >
> > Any thoughts on this would be appreciated.
> >
> >
> >
> > Tom Behler: KB8TYJ
> >
> >
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