Thread: Dual-Z0 Stubs
View Single Post
  #229   Report Post  
Old June 3rd 09, 11:11 PM posted to rec.radio.amateur.antenna
Jim Kelley Jim Kelley is offline
external usenet poster
 
First recorded activity by RadioBanter: Jul 2006
Posts: 666
Default Dual-Z0 Stubs

Cecil Moore wrote:
Jim Kelley wrote:
VF = 0.04 is incredible.


A little knowledge and logic will make it clear.
My 75m Texas Bugcatcher coil is self resonant
at 8.2 MHz which by definition makes it 90 degrees
long. 90 degrees at 8.2 MHz in free space is 30 feet.

The coil is actually 6.5 inches long, i.e. 0.542 feet.

0.542/30 = 0.018 which is the VF of the Texas
Bugcatcher coil at its self-resonant frequency.

The Texas Bugcatcher coil is 4 tpi. The coil with
the VF = 0.04 is 10 tpi. It all makes sense.


Epicycles made a lot of sense, too. So, about that coil. I'm good in
the call book.

ac6xg