Joe,
Well, some of you are lucky enough to have used end fed antennas in
situations where the ground conditions helped your need to ground. My two
very bad end fed wires were 1) in the desert where there is no good RF
ground, and 2) in the Tropics where the rainforest zone has no good RF
ground.
Both suffered from unidirectional response and from high RF levels in the
shack where I could draw sparks off the metal chassis of transmitter.
That tropics problem was the most surprising until a power engineer for
Malaysia explained to me the daily rain leaches out all conductive salts
from the earth, and they long ago washed down jungle rivers to the seas.
They find they have to put down 10 earth rods for grounding and only get it
down to 10 ohms.
In USA, the standard for a "good" ground is usually done with one or two
earth rods and is 5 ohms.
The bottom line is that a balanced (dipole) antenna escapes needing to rely
on earth ground, and any single ended fed antenna needs counterpoise or good
RF earth or both for optimum results.
The balanced antennas (dipoles), have a more easily obtained omnidirectional
response, which is good when you are looking for any contacts as a new ham,
both DX and closer in. They automatically supply the missing half of the
Marconi antenna single wire. Later, when one is faced with camping or
hiking in areas with few or no supports, more simple wires may be the way to
get something working, but is not the easiest antenna to use.
I just saw a number of new hams, when I first came into the game, get bum
starts with random wires; of course, we all lived in the desert and did not
know about RF grounds then.
73,
Stuart
K5KVH
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