Chuck James wrote:
...
Chuck:
I have been tearing apart this place. About a year ago I had
constructed one for 10 meters and had all my notes, etc. Now can't find
a thing.
This link:
http://www.cebik.com/trans/gamma.html
will show you details of a gamma match. It is being used on a dipole
element. Basically, you just use the top half of the element, the half
with the gamma match. Just below the gamma match, you chuck in a 1:1
current balun to choke off the rf which might go to the outside of the coax.
A counterpoise of wire, cut to 1/2 wave at the center freq. of the band
can be attached to the outside of the coax (or coax connector) at the
antenna.
The monopole radiator is a simple 1/2 wave and the length can be
computed from the standard formula: 5904/(frequency in mhz) = length.
The link above contains a basic program to compute the gamma match
dimensions. You should be able to tear the formulas out of the text and
use them manually.
I will see if I can't find the material on dimensions, etc. I had put
together here, still looking.
Regards,
JS