Hi Steve
I have 2 yagi's, a C31XR and a 3el 40M (old KLM) I just
refurbished and put up underneath it. As long as the two
booms are lined up. All is fine. (At least that makes it simple :>)
If they start pointing in different directions, the
20M SWR starts rising.
The 40M antenna's boom is about 30+'. I figure it's close
enough to 1/2 wave on 20M to make a difference. I might be
able to raise the C31XR a couple more feet on the mast - there
is about 8' between them now. I expect we'll try that first but
I don't expect it to make a difference. The 40M is on a
Tic Ring and isn't going anywhere for now (it took 3 months
to align the moon and the stars enough to get it on the tower :>).
So that'll make it hard to hang wires off the end. :>)
At least I have a work around for now - keep 'em lined up while
I'm on 20M. :>)
K7LXC@aol.com wrote:
> In a message dated 10/17/2008 10:18:08 P.M. Pacific Daylight Time,
> towertalk-request@contesting.com writes:
>
> > I swear I've seen stuff on detuning a boom. I even thought I saw
> it in the
> ARRL Antenna handbook. However, I can't seem to anything.
>
> What are the circumstances that made you determine that you need
> to detune a boom? You have 2 yagis and have some destructive
> interaction between them? What are the antennas and what are you seeing?
>
> If the boom is interacting, doesn't that mean that it resonates
> somewhere where you don't want it? How about hanging a piece of wire
> off of each end of the boom? That would change the resonance.
>
> Cheers,
> Steve K7LXC
> TOWER TECH
>
>
>
>
>
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