View Single Post
  #2   Report Post  
Old July 22nd 11, 06:44 PM posted to rec.radio.amateur.antenna
W5DXP W5DXP is offline
external usenet poster
 
First recorded activity by RadioBanter: Jul 2011
Posts: 182
Default Cut length on antenna made from coax cable

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.
--
73, Cecil, w5dxp.com