How long of a ground do you have with the 119 ft antenna?
On Monday, September 15, 2014 12:22 AM, 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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