Topband: Use shunt fed tower

lee at k7tjr.com lee at k7tjr.com
Sat Sep 15 14:00:17 EDT 2018




Chuck,
   I would disagree with you that tower shunt feeding avoids needing radials. Any vertical antenna without some kind of counterpoise will be disadvantaged unless it is close to 1/2 wavelength long. Even then some sort of radials are best. A shunt fed tower does indeed need a good radial field for the best efficiency.
Lee  K7TJR  OR

A shunt fed tower is a vertical antenna so it offers lowest take off angle. Shunt feeding avoids need for radial field.  Any horizontal wire antenna is going to put most of your radiated energy out at high angles, unless you can get it at least a half wavelength of height.  A loop may be a quieter antenna for RX but your existing inverted Vs are no doubt better for TX.
There is some art and experimentation involved in the matching but the results will be worth the effort.  I  would start with your highest antenna for top band, next highes for 80m. Note that your yagis will act nicely as capacitive hats to add to effective tower hight.
Gl es 73, ab1vl chuck




Sent from my Galaxy Tab® A
_________________
Topband Reflector Archives - http://www.contesting.com/_topband



More information about the Topband mailing list