[Elecraft] What about the Zepp antenna?

[Stuart Rohre]

An example of an antenna that does not use a counterpoise, is end fed, and
half wave long, is the end fed Zepp. (Traditionally fed with a balanced line
at the end with only one conductor connected to the antenna.)   Now there
are some authors such as Moxon who challenge its theory of operation, but it
is an old standard antenna in many handbooks, and is never shown with a
counterpoise, or a better term I have heard, "a driven ground"--   (a
conductor insulated and used to reduce RF in the shack by providing at least
a quarter wave at a given frequency, attached to the common point of
transmitter. (ground terminal).)

Counterpoise, in the way many hams use the term, is an element to provide a
reflector for an antenna, but mounted close to the earth, or an element to
complete the "missing half" of quarter wave antennas.  It is a vague term,
and I like the term "driven ground" for those used for elimination of RF in
the shack.  Antenna completion element is rather too long.

Usually, a half wave or longer antenna simply operates against local earth,
which may give it some reflection gain, if elevation of the wire is adequate
to get reinforcement of the radiation from the reflection.  Verticals or Ell
antennas which have part vertical, often use some wires as radials or other
ground completion aids.

The use of a single ground rod at the bottom of a quarter wave vertical does
not have sufficient RF "length" to be an effective RF ground, and is really
used as a static discharge ground element.  Hams often confuse adequate RF
grounds with use of "ground rods" which are a cross over from AC electrical
safety practices.
-Stuart K5KVH