I want try this broadband 80/75-Meter dipole someday when I get some support
lines over a few of my tall fir tree branches.
Originally in the April 1989 QST, reprinted in the NCCC newsletter:
http://www.nccc.cc/jug/2011/jug11jul.pdf
LJ
-----Original Message-----
>From: Larry <lknain@nc.rr.com>
>Sent: Oct 21, 2013 11:25 AM
>To: towertalk@contesting.com
>Subject: Re: [TowerTalk] 80M Inverted V - CW and SSB
>
>Force12 does something similar with its rotatable dipole. Each side of the
>dipole went to box and had 3 coils in series to the feed point. There were 3
>DPDT relays. Each side of the relay would short out a coil on one side of
>the dipole feed. One coil could shift the low SWR point 240 kHz, another
>about 80 kHz, and the last one about 40 kHz (a bit hazy at this point). At
>the input to the box there was a fixed coil across the input terminals and a
>balun to coax. With 3 switches you could adjust the low SWR point to 8
>different places on the band. By default, all coils were inline putting you
>at the bottom of the band.
>
>73, Larry W6NWS
>
>-----Original Message-----
>From: Richard Karlquist
>Sent: Monday, October 21, 2013 1:17 PM
>To: towertalk@contesting.com
>Subject: Re: [TowerTalk] 80M Inverted V - CW and SSB
>
>On 2013-10-21 02:50, Doug Scribner wrote:
>
>> I'd like to find a quick way to switch between the CW and Phone
>> portions of the band. I know I could just set it for SSB and then add
>> a short section to each leg for CW and that works for dedicated
>> contests but is a little inconvenient for everyday use.
>
>On my inverted vee, I cut the wire to tune the antenna to the bottom
>end of 80 meters. I have a box at the top of the tower with 3 relays
>in it that switch in series capacitors in each leg. The series
>capacitors
>tune the antenna upward in frequency. There are 8 combinations
>of relay positions that give me eight capacitance values covering
>3.5 to 4 MHz with low SWR. The capacitors are a pair each of 470 pF,
>1000 pF, and 2200 pF power mica. I also have a 40 meter inverted vee
>at right angles to the 80 meter inverted vee. The feedpoints are
>connected
>in parallel to the capacitor box. The switched capacitors also
>work on 40 meters to cover the whole 40M band with low SWR.
>
>The advantage of this is that you get a really low SWR over the full
>band.
>Passive matching networks can only give you a mediocre match and only
>over part of the band. Then you end up using a tuner in the shack
>anyway.
>
>Rick N6RK
>
>
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