What sort of coax are you using? Thin or thick, and what sort of PL259 - in other words, is it the correct size of coax for the plug.
My approach would be to cut off the plug and test the continuity between outer and inner of the coax. If not continuous, put on another plug.
If continuous, then get rid of the coax.
73
David W Wood
Ham call - G3YXX
FOC # - 1685
Licensed - 1969
-----Original Message-----
From: For blind ham radio operators [mailto:[log in to unmask]] On Behalf Of Tom Behler
Sent: Sunday, August 19, 2012 7:12 PM
To: [log in to unmask]
Subject: Re: G5RV Disappointment
David:
Well, this is interesting.
I'm now trying to figure out what is causing the short, because all of the
connections seem to be as they should be, based on your description here..
Tom Behler: KB8TYJ
----- Original Message -----
From: "David W Wood (G3YXX)" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Sunday, August 19, 2012 12:04 PM
Subject: Re: G5RV Disappointment
> Tom
>
> You should get an open circuit between inner and outer of the coax.
> Basically, with the modern derivative of the true G5RV, you have two top =
> sections each of which joins the ladder line.
> Each side of the ladder joins either to the inner or outer of the coax, =
> hence you should get an open circuit at the PL259.
>
> Wrapping the end of one leg as you describe further destroys the =
> symmetry of what should be a balanced system.
>
> 73
>
> David W Wood
>
> Ham call - G3YXX
> FOC # - 1685
> Licensed - 1969
> =20
>
> -----Original Message-----
> From: For blind ham radio operators =
> [mailto:[log in to unmask]] On Behalf Of Tom Behler
> Sent: Sunday, August 19, 2012 4:48 PM
> To: [log in to unmask]
> Subject: G5RV Disappointment
>
> Hi, all.
>
> Well, I tried the G5RV out at the RV over the week-end, and alas, no =
> joy. I=20
> have some theories about what the problem was, which I'll get to =
> shortly.
>
> First, the good news: The camp site manager had absolutely no problem =
> with=20
> my putting up the antenna, and in fact helped with our initial =
> installation.=20
> So, at least I know I'm good to go if I want to try something else out=20
> there.
>
> Since the guy was nice enough to help with the installation, I decided =
> to go=20
> ahead with his initial suggestion of putting the center on top of his =
> RV,=20
> which is about 50 feet from ours, and much higher than ours. The legs =
> of=20
> the antenna then went across his roof on each side to adjacent trees. =
> He=20
> did wrap one part of one leg around the railing of his RV ladder to =
> keep=20
> things in place. The ladder line then came down from the center of the=20
> antenna on about a 45 degree angle to the PL259feed point connection on =
> my=20
> RV. I'd say the center of the antenna was up about 30 feet, with the =
> legs=20
> up about 15 to 20 feet on adjacent trees.
>
> Overall, my SWR's must not have been good, because the only band I could =
> get=20
> the TS480 auto-tuner to tune it on was 10 meters. Everything else gave =
> me=20
> the SWR no-tune reading.
>
> As for what might have gone wrong, I eliminated a number of =
> possibilities:
>
> 1. I checked my feed line on the RV, and all other jumper connections, =
> for=20
> electrical integrity, and they were fine. I then physically checked the =
>
> connections on the G5RV itself, and they looked fine. I had my XYL =
> confirm=20
> this visually as well.
>
> As for what could have gone wrong, then, my theory is that perhaps the =
> roof=20
> on the manager's RV was metal, or had metal in it, which served to =
> de-tune=20
> the antenna. Wrapping one leg around the RV railing for a turn or two =
> also=20
> might have thrown things off.
>
> Finally, I did one thing in the way of continuity checking that I want =
> to be=20
> sure of with you G5RV experts out there. When you do a continuity check =
> of=20
> the G5RV on the PL259 end, is it correct that you get electrical =
> continuity=20
> across the coax connector? In other words, when I took my continuity=20
> checker, put one lead on the center conductor, and the other on the =
> outer=20
> shield of the connector, I got continuity. I assume this indicates that =
> I=20
> have an electrically complete antenna. Please correct me if I'm wrong =
> on=20
> this.
>
> All in all, it was a rather disappointing situation, but if we can get =
> out=20
> to the RV next week-end, we'll try something else, perhaps in nearby =
> trees=20
> if we can figure out a way to get the center up at a reasonable height.
>
> 73 from Tom Behler: KB8TYJ
>
> --
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