I understand many G5RV's are getting replaced with these antennas.  I
have the Grampy version, that is 100' long on each side, for a total of
300' of wire on each side, all in a 100' on each side package.  Have had
good luck with it.  Their shortest is a bit over 70'.

http://www.k1jek.com/ 

-  

David Wilburn
[EMAIL PROTECTED]
K4DGW
K2 S/N 5982


On Fri, 2008-01-04 at 09:33 -0700, David Yarnes wrote:
> Shaun, Dohn, and All,
> 
> Your proposal to wrap wire around pipe will probably end up being a "bust". 
> In essence, you would just be loading a coil, and it would be very 
> inefficient as a radiator.  Some have tried to use a "helical" approach in 
> order to shorten the overall length, but again that doesn't work all that 
> well either.  An example would be using the old "Slinkey" wire toys that we 
> all probably had at one time or another.  Those can work, after a fashion, 
> but are generally poor performers.
> 
> I disagree about the G5RV also.  That is not a very good antenna, 
> notwithstanding the huge amount of use those antennas get.  The problem is 
> that the G5RV was never intended to be an "all band" antenna, and it is a 
> performer on all but a couple of bands.  Unless you use a tuner, you will be 
> very unhappy with the results you get with a G5RV design, particularly with 
> modern rigs that don't have the advantage older tube-type transmitters had 
> with  pi-network coupling.   The warts that a G5RV has is well documented, 
> and the latest thing I remember reading about it was in a recent issue of 
> Sprat--the Spring 2007 issue.  Therein is a discussion by ex-ZS6BKW, who is 
> famous for originating much of the variations for the G5RV that are in use 
> today.  Paraphrasing his own words, don't expect much from a G5RV unless you 
> at least use a tuner!
> 
>  Unless you want to put up some sort of trap dipole, or a multi-band 
> vertical, your best option is to get a decent tuner and put up a dipole with 
> balanced line feeders.  The 88 foot antenna described by L.B. Cebik on his 
> website (www.cebik.com), is an excellent choice for a simple antenna that 
> will work well on 80 meters through 10 meter.  You can shorten that to 44 
> feet if you want to give up 80 meters.  That will fit in just about anyone's 
> backyard, unless you live in a condo.  The higher you get it, the better it 
> will work.  Just don't use coax, or the losses will eat you alive!  You can 
> coax feed an antenna that is resonant with good results.  But when you try 
> to use it on a higher frequency (like using an 80 meter coax fed antenna on 
> 40 meters), the results turn to mush.  The same antenna fed with balanced 
> line through a tuner will work substantially better at higher frequencies. 
> The resonant antenna (130 feet on 80) works better than the 88 foot antenna 
> does on 80, but the 88 foot version (or the 44 foot version) is intended to 
> standardize your radiation pattern, and is still a decent performer on 80 
> meters.
> 
> Another option would be a remotely tuned vertical on your roof.  Dr. 
> Megacycle (KK6MC), suggested this to me not long ago when he visited my 
> shack.  His advice was to put up a 22 foot vertical, remotely tuned, and 
> using balanced feedline.  This would give you pretty decent performance from 
> 40 meters through 10 meters.  You would need as many radials (random length) 
> as possible.  This was a suggestion as an alternative to my R7 vertical, 
> which is a pretty good performer, but perhaps not as good as the suggested 
> alternative.  I haven't tried that yet, but I'd like to.  I'm sure the 
> suggestion is a good one.
> 
> This may be more than you wanted to hear, but it seemed as if you were 
> struggling to come up with a solution.  Hopefully it helps some in that 
> process.  If wire antennas, or verticals, are just not practical for you, 
> you might want to try a mini-loop.  These aren't nearly as efficient as a 
> good wire antenna, but they are quite small, and the results can often 
> surprise you.  Besides, they are fun to build!
> 
> Dave W7AQK
> 
> 
> 
> ----- Original Message ----- 
> From: "Dohn" <[EMAIL PROTECTED]>
> To: "'Shaun Oliver'" <[EMAIL PROTECTED]>; 
> <elecraft@mailman.qth.net>
> Sent: Friday, January 04, 2008 2:50 AM
> Subject: RE: [Elecraft] dipole antenna efficiency
> 
> 
> > Shaun,
> >
> > For materials needed vs. radio theory, you just can't beat a G5RV antenna.
> > IMHO I've used mine with my K1, K2 and several home brew projs and it 
> > works
> > great time and again.  Yes, you want to get the center up there a ways. 
> > Say
> > around 35-40 feet, but the payoff was good for me.  There are a number of
> > sites out there that have good versions of a very old, classic antenna.
> > Very few parts (all of which can be made with junk around the house.  Very
> > little investment for a sound payoff.
> >
> > Dohn   N8EWY
> >
> > -----Original Message-----
> > From: [EMAIL PROTECTED]
> > [mailto:[EMAIL PROTECTED] On Behalf Of Shaun Oliver
> > Sent: Thursday, January 03, 2008 9:20 PM
> > To: elecraft@mailman.qth.net
> > Subject: [Elecraft] dipole antenna efficiency
> >
> > Hi all,
> > if I were to make a dipole, would coiling it round a piece of plastic
> > piping decrease the efficiency of the thing? I intend on making one for
> > 40 meters, one for 80 meters, and one for 10 meters. I've worked out
> > that1 meter of piping will suffice for each leg of each antenna.
> > thanks in advance.
> > shaun
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