"art" wrote
The above antenna does not have a ground plain
such that it is unbalanced.
_______________

The DLM antenna is a monopole (DLM stands for distributed loaded monopole).
All practical vertical monopoles require an r-f ground or counterpoise of
some kind.

You might want to contact Robert Vincent to confirm for yourself that this
true for the DLM.

And If it didn't, why would he bother to test it at a site with a
near-perfect, salt water ground system?

RF