[TowerTalk] antenna impedence and ground impedence??

[Tom Rauch]

> I am trying to increase the efficiency of a center loaded vertical by
> creating a good ground system.
>
> Based on models the antenna 'should' have a have a total impedance of
> less then 10 Ohms. Yet it reads close to 50 Ohms. I assume the 40 plus
> Ohms is related to ground resistance. Is this a reasonable starting
> assumption??

Dan,

Maybe or maybe not. 50 ohms is very high since any lossless shortened
antenna would have less feed resistance than a 1/4wl antenna...and that's
about 30 ohms or so. So you probably have something wrong. I assume this is
direct series feed with no effort at matching, and you are measuring
resistance right at the antenna.

How do you know what the loss resistance of the loading coil is?
How did you account for the coil in the model?
What type of ground system is it?
Is the antenna in the open away from everything else?
How tall is the antenna?
What band is it on?

73 Tom