[TowerTalk] antenna suggestion?

Chuck Counselman ccc at space.mit.edu
Wed Aug 6 10:12:14 EDT 2003


At 7:36 AM -0700 8/5/03, Al Williams wrote:
>My EZNEC modeling of horizontal dipole indicated off center feedpoint
>does not change the radiation pattern but does markedly change the 
>feedpoint impedance!

Yes, but I bet your model did not (properly) include the _feedline_. 
Unless this feedline is _seriously_ loaded with common-mode chokes, 
it carries substantial common-mode current, which not only radiates, 
it also feeds RF current to the AC power wiring of your house.  The 
result is not only undesired radiation, but also dissipation and a 
high received noise level.

-Chuck, W1HIS


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