"David" wrote
What would you define RF ground as? There seem to be
a lot of different ideas.
______________

A good "r-f ground" has a very small impedance to the flow of r-f current at
the frequency of interest.

A good r-f ground is especially important when using a ground-mounted
vertical monopole radiator, because the path to "ground" is in series with
the r-f current flowing on the monopole. Power consumed by the ground
system is wasted (not radiated as EM energy).

At medium wave broadcast frequencies and in the 160 meter and low HF bands,
a system of ~120 buried radials each about 1/4-wave long provides a
reasonably low-Z ground connection -- probably 2 ohms or less, regardless of
the ground conductivity at the site. This was determined experimentally by
Brown, Lewis and Epstein of RCA in 1937.

Copper water pipes in the home, and even buried ground rods typically are
not good, low-Z r-f grounds.

But many antenna types - such as a dipole - do not need or use such an r-f
ground for efficient radiation.

RF