[Elecraft] I am flummoxed about my antenna

[Michael Walker]

Like other have said, when you 160M antenna looks this broad, you have a
problem.  :)

Somewhere you ground losses have increase and that results in what you are
seeing.

Can you take an antenna analyzer to the base of the antenna and see if you
see the same thing?  If you don't, then change the coax.  If you do, then
check your feed points.

Mike va3mw


On Sat, Dec 1, 2018 at 12:07 PM Craig Smith <ac0ds at sent.com> wrote:

> Lee …
>
> You’re on the right track with changing the coax.  You have some sort of
> resistive loss.  As you note, the “bandwidth” is much higher than it should
> be.    My inverted L had a 2:1 SWR bandwidth of perhaps 35 KHz at most.
>  Your low SWR across the entire band indicates very low efficiency and some
> sort of loss element(s).
>
> After the coax, I’d look at connectors, insulators, etc. etc.   Do you
> have any feed-thrus, suppressors, or other things in the feed system?
>
> I’d suggest first checking the SWR and bandwidth right at the antenna base
> with the coax disconnected.  Use a portable instrument.
>
> Good Luck!
>
> 73   Craig   AC0DS
>
> > On 1, Dec2018, at 9:54 AM, Leroy Buller <lee.buller at gmail.com> wrote:
> >
> > There
> > I tried to get on 160 with my Inverted L last night.  60 feet up and the
> > rest over to a tree, 130 feet total.  About 20 random length radials in
> the
> > yard.  The best I can do with a city lot.  This antenna worked last year
> > very well, but now I get this
> >
> > 12/1/2018 10:46:08 AM     NOTES:
> >
> > Frequency     SWR
> > ---------     ---
> > 001800000     1.3
> > 001810000     1.4
> > 001820000     1.4
> > 001830000     1.4
> > 001840000     1.4
> > 001850000     1.5
> > 001860000     1.6
> > 001870000     1.6
> > 001880000     1.5
> > 001890000     1.5
> > 001900000     1.6
> > 001910000     1.6
> > 001920000     1.6
> > 001930000     1.6
> > 001940000     1.6
> > 001950000     1.6
> > 001960000     1.6
> > 001970000     1.7
> > 001980000     1.8
> > 001990000     2.0
> > 002000000     2.1
> >
> > There seems to be NO resonance at all with this antenna.  Before, I could
> > operate the bottom of the band but nothing above 1850 without a tuner.  I
> > have changed out the coax feeding the antenna which hepl bring signals
> up,
> > but it seems to be a dummy load.
> >
> > Anyone have an idea what is going on?  Shucks, I am out of ideas.  Unless
> > my ground plane has gone wonky
> >
> > My tuner can't find a match for it either.  I have an automatice tuner
> now,
> > but it cannot find a match.  Something is wrong here and I am stumped.
> >
> > Any help from the antenna gurus out there?
> >
> > Lee - K0WA
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