Thanks. I will watch for that when I put it back together.
Kip
On Mon, 2013-03-11 at 19:36 -0400, Joe Subich, W4TV wrote:
> > There is no short from center to ground. I get contact from the center
> > pin of the PL-259 to the tip of the antenna.
>
> Are you saying there is no DC connection between the center pin of the
> coax connector and *ground*? The "ring" (a single turn coil) should
> have connections to both the vertical (whip) and the ground (shell of
> the UHF connector). If there is no connection from the shell of the
> coax (via the bracket) to the bottom of the coil, the antenna will not
> be tuned properly since the coil actually *resonates* the antenna.
>
> The basic Ringo (AR-2) is slightly longer than 5/8 wave - the single
> turn coil resonates the antenna and the tap is adjusted for a 50 Ohm
> match. The ARX-2 stacks a 1/2 wave vertical on top of the 5/8 wave
> antenna and the "stub" between the two provides a 180 degree phase
> shift so the two elements radiate in phase for added gain.
>
> Again, if the coil is not connected at the bottom, the antenna will
> *never* resonate ... more likely it will be "resonant" somewhere
> around 54.5 MHz *as a 1/4 wave vertical* or 160 MHz as a 3/4 wave
> vertical depending on the behavior of the feedline shield.
>
> Couple a grid dip meter to the ring and see if/where you get a dip.
>
> 73,
>
> ... Joe, W4TV
>
>
> On 3/11/2013 6:59 PM, Kipton Moravec wrote:
> > I am testing the antenna on the ground held on a fiberglass pole about 8
> > feet long, so the base is about 8 feet off of the ground and I am
> > holding it up and standing under it.
> >
> > We have a 15 foot piece of RG8X attached to it. There are no other
> > things in the path.
> >
> > That goes directly to an antenna analyzer that makes a graph of SWR. For
> > +/- 50 MHZ centered at 146 MHz we get a straight line 10:1 SWR.
> >
> > We moved the tap a couple of times with no changes.
> >
> > It seems like there are no glued parts that could be assembled wrong.
> > There is no short from center to ground. I get contact from the center
> > pin of the PL-259 to the tip of the antenna.
> >
> > I have completely disassembled the antenna, and am using emery cloth on
> > all the places metal meets metal. I am wondering what else I should do
> > before I reassemble since I got it apart.
> >
> > Kip
> >
> >
> >
> > On Sun, 2013-03-10 at 20:34 -0400, w4lde wrote:
> >> Kip,
> >>
> >> Where are you reading the SWR from? at the antenna or back in the
> >> shack? Three is no LP, HP filters, lighting protection devices in feed
> >> line is there? If so did you eliminate them?.
> >>
> >> What happens after you move the tap point on the ring, SWR change?
> >> Anymore info on how you are testing the SWR would help us.
> >>
> >> 73 de
> >> Ron W4LDE
> >>
> >> On 3/10/2013 8:19 PM, Kipton Moravec wrote:
> >>> I was given a used Ringo ARX2B antenna.
> >>>
> >>> I checked out the manual and set the three measurements to 145 MHz. When
> >>> I tried to tune it, the SWR was 10:1 +/- 50 MHz around 146 Mhz.
> >>>
> >>> The piece of coax looked weathered and I checked it out and it was fine
> >>> with the Ohm Meter and did not seem to change SWR or Ohms when I flexed
> >>> it. But I replaced it anyway.
> >>>
> >>> Found their was no contact through the hair pin to the upper section
> >>> from the Ohm meter. So I replaced the screws and got a good connection
> >>> according to Ohm Meter.
> >>>
> >>> I checked the connections from the end of the coax to all the points on
> >>> the antenna, and it worked as expected with the Ohm Meter. No unexpected
> >>> opens or shorts.
> >>>
> >>> When I tried the analyzer, I still had a 10:1 SWR for +/- 50 MHz around
> >>> 146 MHz.
> >>>
> >>> So now I have disassembled everything and an using emery cloth on all
> >>> the connections and replacing all steel nuts and bolts with stainless,
> >>> and replacing the brass nuts.
> >>>
> >>> What else should I look at before I reassemble?
> >>>
> >>> I really do not understand how I could have such a bad SWR unless I had
> >>> an open or a short -- which I proved I did not have before I
> >>> disassembled. I am not sure what else to look for.
> >>>
> >>> The manual is here:
> >>> http://www.radiomanual.info/schemi/ACC_antenna/Cushcraft_ARX2B_user.pdf
> >>>
> >>>
> >>> Kip
> >>> AE5IB
> >>>
> >>> _______________________________________________
> >>>
> >>>
> >>>
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> >>>
> >>
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