Results may vary! hi hi Where we're you're radials
running? Go with what's best in your situation,
that's how it works. 1
--- NJ0IP <Rick@DJ0IP.de> wrote:
The
> feedpoint of the doublet was about 70 ft. from the
> shack, with one leg
> running towards the street and the other leg running
> back towards and along
> beside the house. Using the leg running towards the
> street I got much
> better performance than when I tied both legs
> together, or used the other
> leg alone.
>
> Again the lesson learned was there are three
> possibilities: left leg, right
> leg, both in parallel. I can only speculate on why
> that is, but now I know
> to always try all three possibilities.
>
> 73
> Rick
>
>
> -----Original Message-----
> From: tentec-bounces@contesting.com
> [mailto:tentec-bounces@contesting.com]
> On Behalf Of Randy Russe3ll
> Sent: Friday, January 20, 2006 9:16 AM
> To: Discussion of Ten-Tec Equipment
> Subject: Re: [TenTec] twin lead fed, 10, band dipole
> w/ 2 low band verticals
>
> A 3/8 wave wire will give almost as good performance
> as the full halfwave. Of course, you have to use
> balanced line to get the match efficiently. A good
> number is 88', if you can swing it. This will give
> satisfactory performance on 80 compared to a 1/2
> wave
> 80 meter dipole. on 80M.(remember, most of the
> current
> is in the part you kept, very little of your current
> is sacrificed in the high voltage/low current ends
> you
> trimmed off. Now, 88'is an Extended double zepp on
> 20
> meters. So this length Doublet will give a
> broadside
> pattern on all bands 80-20, without breaking into
> lobes, and can be aimed in favorite, optimal
> directions. It will cover the same DX area on every
> band. ALSO, don't forget the knife switch! A knife
> switch before entering shack, that disconnects the
> feedline, and shorts it together for a voltage feed
> connection, makes the set up operational for 80
> meter
> (and 160M if you have at least 65 ft. of feedline).
> Your humble doublet, now becomes a vertical, top
> loaded "T" antennas, with a low angle of radiation
> you
> could never get from a dipole on 80. That's hard to
> beat for a backyard antenna. A split lobe pattern
> multi-wave on 10, 12, 17, a 20 Meter EDZ collinear
> beam,a 30, 40, 60, 80 meter dipoles, and two low
> band
> verticals. All in one small city backyard. Moreover,
> no antenna interaction to worry about from akll your
> antennas crowded in a tiny back yard. Ideally yopu
> set
> uptwo of these spaced 90 degrees apart or so and
> cover
> most directions. I believe the Take off angle on 20M
> is 17 degrees with gain at my qth (65 feet up). It's
> about that on 80 meters to if you set up the
> addition
> voltage feed/knife switch arrangement. 66' and 44'
> are
> also good if you don't have the 88 feet.
>
> --- NJ0IP <Rick@DJ0IP.de> wrote:
>
> > Ken,
> >
> > There is a magical length which is about 40 ft.
> per
> > side (plus/minus a
> > couple of ft.) that seems to work great on all
> bands
> > (80 thru 10).
> >
> > I've put this type of antenna up at least 50 times
> > at different locations,
> > using all sorts of lengths due to space
> restrictions
> > at some of the QTH's.
> >
> > Let me show you my "subjective" results I got
> using
> > three versions, all fed
> > with 450 ohm openwire:
> >
> > 1. 80m dipole (~65' per side)
> > 2. Random doublet (about 40' per side)
> > 3. 40m dipole (about 33' per side)
> >
> > #1 worked well on all bands and I could certainly
> > hold my own in pileups on
> > 80 and 40. Of course you lose out to the stations
> > with the beams on 20 and
> > above. Even matched on 160m with my matchbox, but
> > was not very efficient
> >
> >
> .
> >
> > Conclusion: Apparently you can reduce the size of
> > the doublet up to about
> > 35% without losing too much efficiency. Beyond
> > that, you notice the
> > difference.
> >
> >
>
> >
> > 73 ES ALOHA DE KH6/N6KB
> >
> >
> >
> >
> > _______________________________________________
> > TenTec mailing list
> > TenTec@contesting.com
> >
> http://lists.contesting.com/mailman/listinfo/tentec
> >
>
>
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