I never have heard of a successful array using raised radials ... so this
has been a good exercise. Also strongly agree with tuning the verticals to
the intended frequency ..... but this is all with comtek. From the power
dump port, I had 300 foot roll of coax coming back to my meter measuring
the power dump onto the dummy load in my shack!
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On September 2, 2017 12:42:35 PM Gary Johnson <gwj@wb9jps.com> wrote:
> Dan’s simulations and observations are spot-on as usual. So...
>
> 1. For the complete system, observe dump power vs. freq rather than SWR.
>
> 2. Frequency shift between resonance of a free element vs. that of the
> minimum dump power is <50 kHz, which is similar to my own experience. Why
> the manuals say to tune the verticals 150 or 200 kHz low makes no sense to
> me. If you simply tune your elements nearer to the middle of your intended
> operating band, results would be better.
>
> 3. Single radials are not good for pattern, as previously explained. If you
> add a second 1/4-wave radial, feedpoint resistance at resonance will be
> lower and in fact closer to the point design of the commercial phasing
> network. AND, ground losses will be lower. I cannot see what adding
> 1/8-wave radials would accomplish, intuitively nor in simulation. Perhaps
> someone can enlighten me.
>
> -Gary NA6O
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