Hi Dan,

?? In the "Loads (R+JX)" window, you enter a desired position on a
particular wire number, and the value of the load, which presumably
would be a coil or a capacitor. It will tell you where the load
actually got put on the wire, as it must be in the middle of a segment.
You can adjust the number of segments to put the load closer to where
you want, if it didn't come out close enough the first time.

A good way to verify that the load is doing something is to change the
value of the load and look at what happens to the feedpoint impedance,
which you can see in the "Src Dat" (Source Data) window. For example,
if you start with a 10.3 meter vertical, 40mm diameter, 11 segments,
over perfect ground, with the feedpoint (source) at the middle of the
lowest segment, you should find that a coil of 0+j582 ohms gives you
very close to resonance: close to zero imaginary component in the
feedpoint impedance. Raising the coil reactance causes the feedpoint
to become inductive: positive imaginary component. And lowering it
causes the feedpoint to become capacitive.

Cheers,
Tom