View Single Post
  #160   Report Post  
Old May 15th 07, 03:44 AM posted to rec.radio.amateur.antenna
Cecil Moore[_2_] Cecil Moore[_2_] is offline
external usenet poster
 
First recorded activity by RadioBanter: Mar 2007
Posts: 3,521
Default Phase Shift through a 75m Texas Bugcatcher Coil

Jim Kelley wrote:
Reg Edwards' program produces a VF of .0333 and a delay of 26 degrees
for the 75m Bugcatcher coil.


Thanks Jim,

Dr. Corum's formula indicates a VF of ~0.02

EZNEC indicates a VF of ~0.016

The "threaded bolt" method indicates a VF of ~0.006

w8ji indicates a VF of ~0.42 for his 100 turn,
10 inch long, 2 inch diameter coil.

In order to get a valid measurement of the delay
through a coil, the coil needs to be loaded with
its characteristic impedance to minimize the
reflected current. With mostly traveling wave
current flowing through the coil, the delay is easy
to measure.
--
73, Cecil http://www.w5dxp.com