Another approach could be capacitor in one leg of dipole at center
insulator to shorten it for SSB part of band, and shortened by relay to use
dipole in CW part of band. Relay would add just slight weight to center
insulator, 200 pF Silver mica capacitor would "shorten" dipole (rise
resonance point) for about 150 kHz. There are no high voltages present at
center of dipole so ordinar SPST relay would do!
73, Mirko, S57AD
2016-04-25 19:07 GMT+02:00 Bob Farkaly <bob@farkaly.com>:
> I approached this problem 25 years ago to help me earn 5BWAZ. I cut the
> inverted Vee for 80 meters and added a set of 75 meter traps. Voila! Dual
> band 75/80 meter Vee.
>
> 73,
>
> Bob, K9RHY
>
> -----Original Message-----
> From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of CJ
> Johnson
> Sent: Monday, April 25, 2016 12:57 PM
> To: towertalk@contesting.com
> Cc: wt2p@arrl.net
> Subject: [TowerTalk] Rehash of 80 CW/SSB Switchable Dipole/Vee
>
> Howdy-
>
> I have been working on rebuilding my 80M dipole setup for camping and the
> fall/winter contest season.. My one main question is I know that I can make
> the ends for SSB, tune it where i want (most likely 3800).. then on the
> other side of the insulator, add the extra length for CW and tune that
> portion (~3550).
>
> I *don't* have a pressing need to have this remotely switchable or other
> things as discussed in the archives -- a semi fancy matching setup, etc.
> Given that the dipole is temporary in nature, it doesn't pain me to walk
> outside and clip on the CW section when I want to.
>
> That brings me to a couple questions maybe someone can help:
>
> 1) The dipole is being constructed with materials to handle 1500W (balun,
> wires, etc.) -- Will this extra length of wire for CW arc where I "clip" it
> on to add the extra length at the end of the SSB wire running 1500W?
>
> 2) Given that it's "temporary", how would one suggest constructing the
> point
> where I switch from SSB to CW.. Alligator clips? There may be a potential
> for exposure to the elements (mostly rain and some snow).
>
> Thanks,
> WT2P
> _______________________________________________
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