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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