dansawyeror wrote:
All,

I am creating a 'scaled' model of a loaded vertical. The model is
complete and in place. However I immediately realized I had no idea of
the 'theoretical' response. How can I calculate the expected impedance
response of a loaded vertical? It a mid load construction,

the base in #10 solid copper 4 inchs,
the coil is .6 pitch, 1 inch diameter, 5 turns #12, measuring .72 uH,
and the top is 4 inch #12.

The antenna appears to resonate at about 112 MHz.

The instrumentation, a directional coupler measuring reflection is
located at the base, directly under the 'ground plane'. This allows
measuring input and reflected signal strength.

The question is: How can I plot the expected impedance from say 100 MHz
to 130 MHz?

Thanks - Dan

The free EZNEC demo from http://eznec.com will give you the information
you need.

Roy Lewallen, W7EL