*While this is sort of off Ten Tec Topic... Just for the heck of it, kicks
and giggles. Would someone with the software and Big Brain, please tell me
the feed point resistance and approx. SWR of a standard Dipole at 30 feet
height above average terrain and an overall length of 126 feet or 63 feet
each side? We are just wondering what the ladder line (( window line 450
ohm )) is looking into at 3980 KHz... The MFJ-989C and Paragon seem to get
along with this antenna really well. 450 ohm line length is approx. 78 to
82 feet for those who were going to ask.*
* Thanks
from Wade/KJ4WS*
On Sun, Sep 14, 2014 at 11:22 PM, Ronf404 via TenTec <tentec@contesting.com>
wrote:
> I had considered a G5RV but opted instead for a 119' long wire up about
> 65' over a tall tree. Loads under 1.5:1 on all bands from 10-160 with a
> tuner; many bands load at 1.1:1.
>
> Ron Fish, KX1W
>
> Sent from my iPhone
>
> > On Sep 14, 2014, at 23:58, "Bob McGraw - K4TAX" <RMcGraw@Blomand.net>
> wrote:
> >
> > The developer of the G5RV basically states that it is optimized for 20M,
> thus typically having a low SWR of 1.8:1 on that band. Other bands the
> G5RV will have a higher SWR in the range of 5:1. Thus on some frequencies
> the G5RV may be too reactive for the limited range of many internal tuners.
> >
> > Interesting enough, the length of the G5RV is 51 ft on each side of
> center for a total of 102 ft. overall. Then add the 31 ft of 450 ohm
> ladder line. Looking at the configuration we see it is basically two
> inverted L's oriented back to back with the long portion of the L being the
> flat top 51 ft sections and the short part of the L being each side of the
> 30 ft of ladder line. To sum it up, a dipole with reverse drooping ends
> for a total length of 133 ft. Just the right length of most 80M antennas.
> However with the feedline length of 31 ft, considering velocity factor, it
> is approximately 1/2 wave on 20M. Thus the flat top ends each become 3/4
> wavelength on 20M for 1.5 wavelengths overall. The impedance at the center
> feedpoint is ~90 ohms, depending on height above ground. With a 1/2
> wavelength transmission line being fed from a 1:1 current balun this load
> is seen by the transmitter with the SWR on the coaxial segment being
> approximately 1.8:1.
> >
> > While some claim that the G5RV is an all band antenna, we find in
> reality it is a non resonant dipole fed with a section of ladder line from
> a 1:1 current balun. Thus a wide range tuner is required to match this
> antenna on all HF bands where the antenna is approaching 1/2 wavelength or
> more.
> >
> > You are correct, the configuration you have is certainly not a G5RV by
> any degree of imagination.
> >
> > 73
> > Bob, K4TAX
> >
> >
> >
> >
> > ----- Original Message ----- From: "Wade Staggs" <tvman1954@gmail.com>
> > To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
> > Sent: Sunday, September 14, 2014 9:09 PM
> > Subject: Re: [TenTec] Antenna names
> >
> >
> >> *Running 126 feet of wire... 63 feet in each direction... Center fed
> with
> >> 450 ohm Window Line. It is most assuredly Not a G5RV. But my friends
> keep
> >> wanting to call it a G5RV. We can work 80 thru 6 meters with a good
> manual
> >> tuner. Is it the best antenna in the World? Of course not...... But at
> this
> >> Rental Property with some restrictions, we can talk and hear about the
> same
> >> as others using Fan Dipoles and Dedicated to the Single Band Dipoles.
> >> Everything in life is a compromise. Can I unbalance the antenna and
> offset
> >> the Window Line an inch from the dead center and call it a Windom? This
> >> would clear up everyone's insistence that my antenna is a G5RV..... Just
> >> Joking Folks....*
> >>
> >> *
> >> 73 from Wade/KJ4WS*
> >>
> >> On Sun, Sep 14, 2014 at 2:41 PM, Ken Brown <ken.d.brown@hawaiiantel.net
> >
> >> wrote:
> >>
> >>> The Zepp was a one sided antenna, with a quarter wavelength openwire
> >>> feedline to a halfwave wire. ....
> >>>
> >>> Hams are funny about naming antennas. For example, a Zepp antenna may
> have
> >>> been clearly defined as above, but then people make modifications that
> >>> diverge so much from the original meaning of the name it makes no
> sense to
> >>> keep using that name. Make it into a dipole, and call it a "Double
> Zepp."
> >>> There is no way a Double Zepp could ever be used the way a "real Zepp"
> was
> >>> used on a Zeppelin....
> >>>
> >>> Or make the horizontal wire longer, and call it an "Extended Zepp." But
> >>> then it is not the length it needs to be a normal Zepp. So why keep
> calling
> >>> it a Zepp?
> >>>
> >>> Then there is the G5RV antenna. The "inventor" G5RV said there is no
> such
> >>> thing. He built a dipole and experimented with various lengths of
> ladder
> >>> line and coax, to try to find a combination that worked good on
> multiple
> >>> bands. He said it was just a dipole, but the ham community called it a
> >>> G5RV. Now there are hams who claim that a specific length dipole, with
> >>> specific lengths of ladder line and coax feeding it are "genuine G5RV
> >>> antennas" and the anything else is not. Other hams think that any
> dipole
> >>> fed with ladder line is a G5RV.
> >>>
> >>> DE N6KB
> >>> _______________________________________________
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> >
> >
> >
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