Re: [TowerTalk] G5RV

[Mahlon Haunschild <mahlonhaunschild@cox.net>]

... but Dino, if you remove the coax/balun/twinlead then the antenna is 
no longer a resonant antenna system on 20 meters, as designed (e.g. it's 
no longer a G5RV).  It's just a random length dipole fed with low-loss 
ladder line by an antenna matching network.  No rocket science there.

The advantage of the G5RV is that it's a resonant antenna that exhibits 
some gain in certain radiation lobes, but only on 20 meters.  That's all 
Louis ever intended it to be, I believe.  Everything else written about 
the antenna is marketing hype, IMHO.  But you don't have to take my word 
for it; go back and read his article in the Compendium instead.

regards,

Mahlon - K4OQ

Dino Darling wrote:

> Hornets nest....yep!
>
> I was told to REMOVE the balun (mine was a Van Gordon voltage balun) and 
> hook the coax directly to the ladder line.  I instead cut my antenna at 
> the center insulator and got rid of the coax/balun/twinlead and 
> installed 450 ohm ladder line directly to a tuner and each 51' leg.  It 
> works MUCH better than the G5RV ever did!!!
<snip>
> At 07:07 PM 01/03/2004 -0500, you wrote:
>
> > All,
> >
> > I recently put up the G5RV that my wife purchased for me at 
> > Christmas.  After putting it up and taking it down 4 times, I must 
> > confess that I am at a loss.
> >
> > Some background:
> >
> > My property is large enough for a G5RV, but not for an 80 meter 
> > inverted vee.  So I elected so ask "Santa wife" for the G5RV (one of 
> > the premanufactured ones available at the local ham radio store).
> >
> > The antenna is supported by approximately 33' of mast at the center 
> > and slopes down to approximately 11 feet at the ends.  (High enough to 
> > keep the kids out of it.)  The ladder line is held away from the pole 
> > all the way down approximately 5 or 6 inches with a couple of wooden 
> > standoffs that I fabricated.  I also tried coiling about 7 or 8 - 6" 
> > turns of coax at the feed point per a suggestion I saw on a web site 
> > although this didn't seem to have any impact on the performance or 
> > SWR.  I also tried changing the length of coax feeding the antenna, 
> > but still not difference.
> >
> > My concern is this, while I get a good SWR on 20 (about 1.5 at 
> > 14.200), I am unable to make the antenna work on any other band 
> > without using a tuner.  The SWR on any other band is at least 4:1 or 
> > higher.  I had a G5RV about 20 years ago and seem to remember that it 
> > had a decent SWR on 80, 40 and 20.  I tried to play with the length of 
> > the wire, adding several lengths to the ends, but still could not find 
> > a resonate point on any other band.
> >
> > While I don't mind using a tuner, I am wondering if I am missing 
> > something.  I verified all of the dimensions (102' of wire and 31' of 
> > ladder line).
> >
> > Any idea?  I hope that I am not stirring up a hornets nest with this 
> > question.
> >
> > Thanks in advance...
> >
> > KD8OK  -  Mike
>
>
> Dino...k6rix@earthlink.net

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