GW asked (clip):
How do you determine the quality of an antenna ground at HF
on an absolute basis? Not how well have I maximized what
Mother Nature gave me at my QTH by adding radials, but
how good is my ground compared to other stations' grounds
at other locations?
______________

A low-resistance ground connection for a transmit antenna is important to
the received signal level only when the antenna design requires it as a
reference for its driven element, such as with the vertical radiators used
in MW broadcasting.

Most HF/VHF/UHF transmit antennas do not need, or use an earth ground for
efficient radiation. As practical proof of this, recall that airborne
antennas have no connection at all to earth ground, but still work just
fine. And the transmit antennas used in commercial FM & TV broadcast are
installed at the top of a tall tower, many wavelengths (and ohms) above
earth potential. The tower is grounded for safety reasons, but the
radiation patterns and received signal levels from those antennas would be
the same even if that tower was not grounded.

RF

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