[Fwd: Re: Elecraft. G5RV Question]

[Rick Hampton-2]

Sorry, Don.  I didn't mean to spam you, I forgot to make sure the TO:
address was going to the reflector!

I meant for this to go out to everyone.  Sorry....

-------- Original Message --------
Hi, Guys.

The thing you have to remember is that the G5RV originated in the days
of final
amplifiers built with vacuum tubes and adjustable pi-output networks.
The
pi-output network itself functions as a narrow-range "antenna tuner."
I've used
G5RV's quite successfully without an external antenna tuner on all bands
available on my trusty Kenwood TS-820s.  I found the G5RV to work as
advertised,
with the load presented to the rig falling within the tuning range of
the output
network.  So, the claims of a G5RV not needing an external tuner for
multi-band
use can be fulfilled with an older rig.

However, using a G5RV as a multiband antenna on a modern-day,
solid-state rig
that always expects to see a 50-ohm, non-inductive load simply won't
fly.  Like
Don said, it was originally designed as a 20-meter antenna, so you can
expect
reasonable performance there.

I agree with Don on the final recommendation.  Until you get an ATU,
keep the
multiple dipoles.  Experiment with the G5RV (and other antennas) after
you get
an ATU.

Regards,

Rick Hampton, WD8KEL

W3FPR - Don Wilhelm wrote:

> While the G5RV has a lot of advocates for multiband use, it works much
> better if you bring the parallel feedline all the way to the tuner.  When
> used for multiband, with coax and the matching section, you will likely find
> a higher than desirable SWR on the coax except on 20 meters.  I have found
> the claims for the G5RV antenna to be highly exaggerated.  For good unbiased
> information on the G5RV (or most any other antenna for that matter) check
> out the wealth of information gained by modeling at L B Cebik's website
> www.cebik.com.
>
> Your multi-dipole will be more efficient on 80 meters, and can be fed
> directly with coax and no tuner.  If I were in your shoes, I would leave
> well enough alone unless there is some other overriding reason to change it.
>
> 73,
> Don W3FPR
>
> > -----Original Message-----
> >
> >
> > Hi Guys, my main rig is a K1 feeding a multi dipole for 80/40/20 with no
> > ATU. I am thinking of taking down the dipoles and trying a full size G5RV.
> > Questions:
> >
> >    Will the KAT1 ATU tune up on all bands from 80-15m
> >
> >    I will be using about 80 feet of 50ohm coax to get from the matching
> >    section to the rig, am I going to get big losses in the coax due to the
> >    high SWR on most bands? The beauty of the G5RV is that it can be fed
> >    with coax but with only 5W I don't want to waste all the power in the
> >    feeder.
> >
> >    I intend to build the G5RV myself (like all of my antennas), how
> >    accurate does the length of the matching section have to be? does it
> >    need tuning in some way. Can I use any insulated wire for the open wire
> >    section?
> >
> >
> > The multi dipoles have been great performers but it's a lot of wire up
> > there and very heavy, I thought that with the G5RV being one single top
> > wire it will be lighter and I may be able to get it higher.
> >
> > Any thoughts would be appreciated.

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