And, you'll find that the resonant frequency will change by moving the wire
closer to, or away from, the tower base.
73,
Joe
WL7M
At 06:45 PM 22-10-2002, you wrote:
>Yes,
>Shorten the shunt wire [gamma] to about 45 feet.
>All that hardware on top of the tower makes the tower look very long to
>the feedline!
>Not exactly sure what capacitance will tune it at that gamma length,
>but, if you used an antenna analyzer, you'd get it right in not much
>time at all !
>Good luck,
>Don
>N8DE
>
>Jim Johnson - KC4HW wrote:
> >
> > Hello Everyone,
> >
> > Need a little help with shunt feeding a 80 trylon self supporting
> tower. On
> > this tower there is a 4 elements for 20m on 36' boom with 4 elements
> > interlaced for 15m. At 87' is 5 elements for 10m on 24' boom and at 95'
> > is 2 element on 40m.
> >
> > The shunt wire (12 gauge) is at 65' space approximately 4' from the
> > tower. Have determined that the approximately capacitance at the feed
> > point is 280pf, however the lowest SWR appears to be about 3 to 1.
> >
> > Can anyone suggestion something to improve this situation?
> >
> > Thanks!
> >
> > Jim Johnson, KC4HW
> > Melbourne, Florida
> > http://www.kc4hw.net
> > DXCluster RF Connection: 144.95
> > Telnet://kc4hw.homelinux.net:8000
> > _______________________________________________
> > AN Wireless Self Supporting Towers at discounted prices,
> > See http://www.mscomputer.com
> >
> > Wireless Weather Stations now $349.95. Call Toll Free,
> > 888-333-9041 for additional information.
> > _______________________________________________
> > Towertalk mailing list
> > Towertalk@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
>_______________________________________________
>AN Wireless Self Supporting Towers at discounted prices,
>See http://www.mscomputer.com
>
>Wireless Weather Stations now $349.95. Call Toll Free,
>888-333-9041 for additional information.
>_______________________________________________
>Towertalk mailing list
>Towertalk@contesting.com
>http://lists.contesting.com/mailman/listinfo/towertalk
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