as I said before, all the years I was on a second floor I never ran an RF
ground and that includes with the cobra ultralite. I never had a problem. If
it was a lightning ground I wouldn't have tried it but if lightning gets
that far that it gets to an RF ground on the radio, the radio's dead, the
house is a lost cause and you're likely dead.
----- Original Message -----
From: "Tom Fowle" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Wednesday, August 19, 2015 12:16 AM
Subject: Re: Question About Cobra Ultralite Senior Antenna
> 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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