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Old October 26th 07, 12:15 AM posted to rec.radio.amateur.antenna
Dave Dave is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 797
Default Slow wave antenna design for top band


"art" wrote in message
ups.com...
On 25 Oct, 14:47, Cecil Moore wrote:
Denny wrote:
Dunno... Interesting problem...


Not really - a helix can slow down a wave by
a factor of 50 or more. Approximately a foot and
a half of 75m Texas Bugcatcher stock will be self-
resonant at 4 MHz. That's 90 degrees of antenna
stuffed into about a foot and a half of coil.
90 degrees at 4 MHz is 61.5 feet. The VF of that
coil is 1.5/61.5 = 0.024. Actually, pretty simple.
--
73, Cecil http://www.w5dxp.com


Yes Cecil I see where you are coming from
but and it is a big but the turns must be
exposed to radiate and it is that that one
must not lose sight upon
Art

try a ctha that may do what you want.