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Old May 24th 09, 04:08 AM posted to rec.radio.amateur.antenna
Richard Clark Richard Clark is offline
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First recorded activity by RadioBanter: Jul 2006
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Default Piano Wire Antenna for Experimental Rocket

On Sat, 23 May 2009 16:40:22 -0700 (PDT), mr1956
wrote:

Maximum
velocity was about Mach 3 which is why a conventional antenna cannot
be used as it will be melted by friction.


Would seem to be at odds with:

This new antenna will be mounted
totally on the exterior of the airframe and angled back only about 10
degrees to give a better radiation pattern.


At Mach 3, I seriously doubt you could hold it as erect (80 degrees to
the fuselage) as you might try with smaller wire (in fact, I would say
it would be plastered down).

If your telemetry is directly below its ascendance, you might try a
full-wave or longer antenna trailing below (if it can withstand the
propulsion heat). If that is not possible, look into an inverted F:
http://www.qsl.net/kb7qhc/antenna/In...%20F/index.htm
(it doesn't have to be a thick antenna).

73's
Richard Clark, KB7QHC