The 'coil' is used for decoupling. A coaxial choke. The length of the coax
and its capacitance needs to be included in the calculations. Which I did
not do. It was a wing it job.
The length of about 190 foot is to make the antenna 'tunable' on the other
bands. With a tuner (pi-net) I can run this antenna everywhere from 1.8 to
30 mhz. But on 80 CW I need to have several caps to ground to allow the
pi-net to work that band.
Dan/W4NTI
----- Original Message -----
From: "Jeff Clarke" <ku8e@bellsouth.net>
To: "SECC" <secc@contesting.com>
Sent: Sunday, December 01, 2002 1:03 PM
Subject: Re: [SECC] Feeding 160 Meter Antenna
> Just wondering....
>
> You said you are base loading your 160 meter inverted L that was 190 feet
long. If
> it was greater than 1/4 wl wouldn't you want to have a capacitor (not a
coil) to tune
> the antenna ??? Maybe I am missing something since I'm not an expert on
this....
>
> Jeff
>
> =========================================================
>
> Jeffrey D. Clarke 770-218-0278 email : ku8e@bellsouth.net
>
>
> Please see my resume webpage at http://home.bellsouth.net/p/PWP-ku8e
>
> =========================================================
>
> ----- Original Message -----
> From: "Dan/W4NTI" <w4nti@mindspring.com>
> To: "Bill Coleman" <aa4lr@arrl.net>; "Jeff Clarke" <ku8e@bellsouth.net>;
"SECC"
> <secc@contesting.com>
> Cc: "MRRC Mailing List" <mrrc@contesting.com>
> Sent: Saturday, November 30, 2002 12:43 PM
> Subject: Re: [SECC] Feeding 160 Meter Antenna
>
>
> > From my experience on 160 I think the trick is getting as much vertical
> > properties as possible.
> >
> > Feeding a "T" will mean several excursions to get it right. They tend
to be
> > a bit touchy from what I recall. Course it should play well.
> >
> > FWIts worth department. I put up a Inverted L, about 190 foot total
> > length. It goes up about 50 feet and out the rest. Towards the north
this
> > year.
> >
> > My only ground is a 8ft copper rod and the ground return of my run of AC
> > line from the main house fuse box out to the shack. Which is about 140
foot
> > from the box to the shack ground.
> >
> > I use a 8 turn coil about 6 Inches across that hooks right to the base
of
> > the antenna. The shield, of course, goes to ground. The length of
RG-213
> > cable I ended up with was about 25 foot. Nothing really measured. Cut
and
> > try mainly.
> >
> > With NO TUNER I can adjust resonance anywhere in 160m by
> > lengthning/shortning the wire.
> >
> > Give it a shot. Worked for me in Ohio and two places here in Alabama,
> >
> > See ya in the contest.
> >
> > Dan/W4NTI Alabama
> >
> > ----- Original Message -----
> > From: "Bill Coleman" <aa4lr@arrl.net>
> > To: "Jeff Clarke" <ku8e@bellsouth.net>; "SECC" <secc@contesting.com>
> > Cc: "MRRC Mailing List" <mrrc@contesting.com>
> > Sent: Friday, November 29, 2002 10:28 PM
> > Subject: Re: [SECC] Feeding 160 Meter Antenna
> >
> >
> > > On 11/29/02 9:17 PM, Jeff Clarke at ku8e@bellsouth.net wrote:
> > >
> > > >I was going to try to put up a antenna for the ARRL 160 contest and
got
> > to
> > > >hinking - why not use the zepp I use for 80-10 meters on 160 by
shorting
> > > >the 450 ohm
> > > >feedline , sticking my antenna tuner outside and running a few
radials.
> > >
> > > I have a 125 foot doublet that my tuner can handle on 160m. I made
about
> > > 200 Qs with it in last years ARRL 160 with 100 watts. You might just
try
> > > tuning it up directly.
> > >
> > >
> > > This year, I'm going to try to shunt feed the tower on 160m. I have 13
> > > 1/8 wave radials ont the ground, if I can drive the tower, it ought to
be
> > > at least as effective as the doublet.
> > >
> > >
> > >
> > >
> > >
> > > Bill Coleman, AA4LR, PP-ASEL Mail: aa4lr@arrl.net
> > > Quote: "Not within a thousand years will man ever fly!"
> > > -- Wilbur Wright, 1901
> > >
> > > _______________________________________________
> > > SECC mailing list
> > > SECC@contesting.com
> > > http://lists.contesting.com/mailman/listinfo/secc
> >
> > _______________________________________________
> > SECC mailing list
> > SECC@contesting.com
> > http://lists.contesting.com/mailman/listinfo/secc
> >
>
> _______________________________________________
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