Lynn,
I'd advise against it, or at least recommend that you document the VSWR
bandwidth and F/B performance of the antenna before and after your
proposed modification to be sure that no unintended degradation has
occurred!
Multiband Yagis using elements grounded to the boom are subject to
spurious undesired resonances. This is caused by currents flowing in
adjacent elements and the boom - for example 1/2 half of the last
director, the intervening boom section, and the opposite 1/2 of the
adjacent element. The "books" you refer to probably referred to monoband
Yagis where such spurious resonances are much less likely.
I'd don't want to discourage you from trying your idea - but to encourage
you to do so with due attention to detail.
73!
Frank
W3LPL
donovanf@sgate.com
On Sun, 6 Oct 1996, Lynn D. Osterbur wrote:
> Now that I have my KT34XA on the ground for the 3rd time, I was thinking
> of grounding the center of the parasitic elemnts to the boom. The books
> say there will not be any change in performance. I was wondering about
> static build up. Anyone have any experience or comments regarding
> grounding or not grounding the reflector and the directors?
> Thanks 73 Lynn NO9Z
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