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Old May 30th 09, 12:31 PM posted to rec.radio.amateur.antenna
ml ml is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 225
Default spider at height

hi

I was reading about a few different variants of the spider beam type
multiband HF antennas.

A few of the designers seemed to indicate to me that the antenna
works 'best' ground mounted at around 30-40 feet or so but not
greatly higher.

When I asked if it would work 'ok' on the roof of my building at
100+ feet was told no way over 40ft it would work poorly



It started me thinking, I couldn't really see why it wouldn't
work or work better at height, or at least as good

I do understand potential for change in radiation angle, but not why
the antenna gain would take a dive



the kinds i've seen seemed to be either moxon like kinda
simular so I would think that these designs would be fine at
height if not better (for certain things)


anyone think of something i might have overlooked in the spider like
designs that would actually 'kill it' at 100ft? (talkin about
gain/electrical performance NOT wind damage)


just couldn't see anything that would prevent it from working at
height




thanks