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Old March 26th 12, 01:39 AM posted to rec.radio.amateur.antenna
Wimpie[_2_] Wimpie[_2_] is offline
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First recorded activity by RadioBanter: Mar 2008
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Default Helium balloons to lift DIY 5/8 antennas

El 25-03-12 23:22, MLNJ escribió:
Looking at portable and easy to deploy method of putting up a 5/8 omni
directional antenna for CB/10-11m trans/rec. Is hooking up an antenna
wire to a helium balloon on the "top" end and connecting it to coax at
the "bottom" a possible option? Obviously there are many
environmental limitations with the concept, and it is a strictly
single use application. But for camping or emergency back up use, the
concept sounds at least plausible. Anyone have any technical reasons
why this is not feasible? Better yet, anyone have any experience with
anything similar?


I would not use a 5/8 antenna, as this requires 1/4 lambda radials,
and has (virtually) no advantage over a half wave. A half wave wire
end-fed antenna design can be used without radials mostly.

If you use grease impregnated wire, or monofilament line to tie the
antenna to the balloon, it will not reduce efficiency, even under wet
conditions. Of course you could also use a plastic insulator. you may
know raising the antenna will enhance ground wave propagation, but
above a certain height will not improve ionospheric propagation.

Why not use a fiberglass mast?


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Wim
PA3DJS
www.tetech.nl
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