close up of parabolic driven element, reflector, tangental guide
experimental 1/4 wave 70cm cylindrical parabolic (circular 4' diameter)
This got about 10db gain (over the bare quarter wave antenna) when the driven element was in exactly the right spot. Unfortunately, this spot is very small and not where predicted, probably due to irregularities and the circular aberation. If I get rid of the hanging rod, I could hang them directly from the ceiling and get a true parabola, with possibly better effectiveness, but no ability to aim.
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