Hi CJ,
Simplest is to loop the wire thru the end insulators and back on itself. Build
the dipole to resonate at the lowest frequency of interest. To resonate at a
higher frequency, fold the wire back on itself. Use cable clamps or split bolts
to secure it. Or, if you just twist the wire back on itself, there's nothing to
drop (and lose).
I use split bolts to secure the ends of my 4-wire 80m cage inverted vee. Its
response is broad enough that it works fine from 3.5 to 4.0 MHz w/o adjustment.
With about 80 feet of coax and no balun/choke, I drive it against ground on
160m. I use a SPDT vacuum relay to do the switching. My rig's ATU tunes it fine.
vy 73,Bryan WA7PRC
On 4/25/2016 11:57 AM, CJ Johnson wrote:
> 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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