You need to keep the RF off the OUTSIDE of the coax. Buy or build a 1:1 Balun
(or a "Line
Isolator" as they're sometimes called) as Rich suggests below. You can do it
by neatly wrapping
15-20 turns of coax around a 6 to 8 inch form or buy a stack of ferrite beads
(enough to cover
about 12 inches of coax) and put them on the coax where you connect into the
Titan's pig-tail.
There are a couple manufactures that make one with SO-239s on either end which
would be a good
match for the Titan, since most people use a double-female coupler there anyway.
I had the same problem with my dipole (and to a lesser extent with my Titan) --
my rig went nuts
when I ran over a couple hundred watts on 40 or 75m. The balun totally cured
it!!
Joe,
N3JI
--- "R.Measures" <r@somis.org> wrote:
>
> On Jul 25, 2004, at 9:38 AM, Patrick Hoppe wrote:
>
> > Hello all,
> >
> >
> >
> > I have a problem with RF feedback on 20, 40, and 80 meters. If I run
> > my
> > AL-811H, I get RF feedback on those bands. Nothing on 10 & 15.
> > Everything
> > is grounded very well, but it is still there. Any ideas?
> >
> Hello, Patrick --- Do you have a coaxial choke balun at the antenna end
> of the feedline?
> >
> >
> > Particulars:
> >
> > Kenwood TS 570D
> >
> > Gap Titan DX Vertical
> >
> > Ameritron AL-811H
> >
> > Heil Pro-set Plus head phones & boom mic
> >
> >
> >
> > Thanks,
> >
> >
> >
> > Pat
> >
> > WW9R
> >
> > _______________________________________________
> > Amps mailing list
> > Amps@contesting.com
> > http://lists.contesting.com/mailman/listinfo/amps
> >
> >
> Richard L. Measures, AG6K, 805.386.3734. www.somis.org
>
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
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