Correction, 100X the loss.
The deal difference between a single ground rod and a BC station ground
will be about 6 dB.
Dave WX7G
On Dec 12, 2012 1:13 PM, "DAVID CUTHBERT" <telegrapher9@gmail.com> wrote:
> 20 dB implies that the ground system loss is 10X the inverted-L radiation
> resistance.
>
> This would result in an input resistance of 250 ohms and a minimum VSWR if
> 5:1.
>
> I don't think that is what the real deal will deliver, do you?
>
> Dave WX7G
> On Dec 12, 2012 12:54 PM, "Guy Olinger K2AV" <olinger@bellsouth.net>
> wrote:
>
>> 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
>>
>
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