Greetings all-
I am trying to figure out the size and dimensions of a coil, made from 4AWG
copper, to bring the resonant point of a vertical down from 3.900MHz to
3.800MHz.........
I need to figure the size based on a value of 0.5uH...........I'd like to use
a high Q air wound inductor .....I was referred to look in look in the ARRL
book for making solenoid coils but cant find it-
Can someone please tell me what they think the size of the coil should be??
ie: The number of turns, the diameter of the coil, and the spacing between
the coils...........I am planning to just put in line between the antenna
feedpoint and the feedline- but I'd like to start with a coil in the ball
park-
Right now, I am just feeding the antenna with any base coil at all- Most
resonant point is around 2.2:1 due to impedance match between 50 ohm coax and
38 estimated impedance of antenna-
Here are the specifics on the antenna:
80 meter vertical
currently resonant at 3.900MHz
Target Freq 3.800MHz
Radiator is 44 feet tall
Radiator is made up of 2 1/8 diameter aluminum radiator tappered up to 1 1/4
inch at the top
three 20 foot top hat wires at 45 degree angle at 39.5 feet
60 1/4 wave ground radials
Ground mounted
(I know I can pull out the top hat wires, to let' say a 35 degree angle, to
lower the resonant point but I want to try a coil instead)
Any help is greatly appreciated!
73 Paul N0AH
--
FAQ on WWW: http://www.contesting.com/towertalkfaq.html
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
Search: http://www.contesting.com/km9p/search.htm
|