Thread: Cut length on antenna made from coax cable
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Old July 23rd 11, 06:53 AM posted to rec.radio.amateur.antenna
Jeff Liebermann[_2_] Jeff Liebermann[_2_] is offline
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Default Cut length on antenna made from coax cable
On Fri, 22 Jul 2011 10:44:01 -0700 (PDT), W5DXP
wrote:

On Jul 22, 11:51*am, Jeff Liebermann wrote:
*However, I'm not sure if the driven
element cut length is the free space 1/4 wavelenth, as it would be
with a metal rod coax antenna, or if I should include the 0.67
velocity factor of the coax dielectric covering the center conductor.
Is it 19.2" or 12.9" for the driven element?

Use the 0.67 VF on transmission line currents. Use VF = 0.95-0.97 for
antenna currents.

Thanks. That's what I was looking for.
--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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