With the following caveat: The very sparse and short buried radial systems
he is showing are FAR more lossy in practice than shown in his gain tables.
Four twenty foot buried radials beneath a 1/4 wave L on 160, could place
you down 20 dB. You really can't do that as your 160 meter counter poise
and expect decent results. You can end feed the same wire on 80/40/30
meters (full wave worth of wire in the L on 80m) with four buried 20 foot
radials and it will be an excellent antenna. This is due to the high Z
feed at the ground with current max AWAY from the feed point.
A quarter wave L on 160 MUST deal with the counterpoise loss issues, one
way or another.
73, Guy
On Wed, Dec 12, 2012 at 2:07 PM, Ashton Lee <Ashton.R.Lee@hotmail.com>wrote:
> This wonderful article written by L.B.Cebic W4RNL sure can make you a
> believer in a simple wire inverted L. It is the last antenna discussed.
> http://www.users.on.net/~bcr/files/backyard%20wire%20antennaes.pdf
>
> A $3 wire pulled up into a tree will beat just about any commercial
> antenna… because it is longer. So on low bands it has increased band width
> and efficiency, and on higher bands it has gain. Yes, I know , some of that
> high band gain is horizontally polarized, but that's not all bad. Just get
> the vertical portion 33 feet or so and you'll be happy as Larry. The
> article shows that an extensive radial field may not be necessary.
>
> And a wire is a lot less visible than a big hunk of aluminum. Without
> trees, just top load a 43 foot (or possibly even shorter) vertical. The top
> loading could be a T just as easily as an L. People can argue that one all
> day.
>
>
>
>
> On Dec 12, 2012, at 11:30 AM, k6xt <k6xt@arrl.net> wrote:
>
> > My first antenna, still in use, on moving to CO is a GAP Titan,
> advertised to load up 80 thru 10 including WARC bands. The Titan is a bit
> shorter than Voyager, 28 feet or something like it. The advertising is
> correct, it loads up 180 thru 10.
> >
> > But wait. Is it effective on all those bands? No.
> >
> > On 80 its a dummy load. On 40 it works extremely well after I added a
> one foot extension to the bottom wire that encircles the antenna. In some
> cases it is the equal of my shorty HyGain 40 at 70 ft - which probably says
> more about the HyGain than the GAP. For the rest its better on the
> traditional bands than the WARC bands. It worked a lot of DX for me for the
> couple years it was my only antenna.
> >
> > Carrying my experience to the few feet taller Voyager, and from what
> I've been told by Voyager users, the ant will meet its spec which is to
> load up on the low bands. Expectation wise I'd expect it to be like the
> Titan. It loads up but is otherwise a dummy load. Maybe with a batch of
> radials it could be made to work as well as any other extremely short
> vertical or GP.
> >
> > Not to say there's anything wrong with GAP. My brother had up an R7
> which he rated about like the GAP on bands both cover. Those multiband
> halfwave short verticals work but you get what you pay for.
> >
> > 73 Art K6XT~~
> > Success is going from failure to failure without a loss of enthusiasm.
> > ARRL, GMCC, CW OPS, NAQCC
> > ARRL TA
> >
> > On 12/12/2012 10:00 AM, topband-request@contesting.com wrote:
> >> With the prospect of downsizing and moving into senior housing in the
> future
> >> I am starting to look at vertical antennas that will allow me to
> continue
> >> this wonderful hobby.? I have heard "some" good things about the GAP
> series
> >> of antennas but the company says they do not need radials on most of
> them
> >> and that worries me.? Over the years I have become very skeptical about
> >> claims and the other BS put out by most companies ( maybe it is a
> function
> >> of age I dunno) so I wonder if these antennas really work.? The two
> antennas
> >> that I am interested are the Voyager DX for 160/80/40? and the Eagle DX
> for
> >> the rest of the bands.
> >>
> >> So my question is.... does anyone have actual experience with these
> antennas
> >> (especially the voyager) as compared to other antennas for a specific
> >> frequency.? Now guys .. I know you cant really compare a 6 element beam
> to a
> >> vertical of this kind but I am talking about a comparison that is
> >> realistic.. like how does it hear, tune, match & get out compared to
> >> something like another vertical or a dipole up some reasonable distance.
> >>
> >> I sure hope this has not opend another can of worms.. some how I seem
> to do
> >> that .. private emails are ok..especially it the topic gets out of hand
> and
> >> we get a large volume of comments (Tree please dont shoot me before
> >> Christmas my wife will miss me.)
> >
> > _______________________________________________
> > Topband reflector - topband@contesting.com
> >
>
> _______________________________________________
> Topband reflector - topband@contesting.com
>
_______________________________________________
Topband reflector - topband@contesting.com
|