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