[Elecraft] Good Low Horizontal Loops - questions

[Stuart Rohre]

I prefer to refer to twin conductors as parallel line, since indeed, balance
is not guaranteed by its use.  Balanced line is only balanced if the
currents are equal in both sides.  At an unbalanced source, you would not
expect to be able to gain equality in the current in the parallel feeders.

Fascinating however, was the L. B. Cebik computation or measurement of Zepp
feeders.  He found that the open circuit side of the parallel line was only
10 per cent out of equality with the side connected to the end of the half
wave antenna.  At least, that is the way it read.  A pair of current meters
would help one check line balance, as they would equally upset the two sides
of the line, and at least allow a relative comparison.

A good experiment would be to see what line current you read with one meter
of a pair, and no meter in the other side of the line; and then connect both
meters, one in each leg, the same distance along the parallel line.  (Am
looking for my collection of meters now with the thought of comparing the
Les Moxon indictment of End Fed Zepp type antennas to other Off Center Fed
types.)

  There are installations that are more easily handled by off center feed or
end feed.  However, from modeling various OCFs, as Cebik has done, I think
the penalty of end feed is a distortion of the radiation pattern, and I
prefer to have a near omni pattern.  Those nearer one coast or the other may
well benefit from end feeds or OCF feed, if you  wish to favor land side
rather than ocean.  But, this brings up another fascinating question.  Does
an OCF antenna at the beach gain back pattern on the short side, if that
side is nearer the water?  That is, with the wire at right angles to the
surf line.

No single antenna is sufficient for all ham use.  Some come closer to our
objectives at a band or time, (such as working DX) than others.  But, if
limited space or limited numbers of antennas are the requirement, there are
variations on balanced antennas that will give one a combination of DX
capability and short skip operations.

Our local club's contribution to the art of horizontal loops is treating the
legs as individual pieces of wire, easing the installation of massive
amounts of wires.  Operationally, they work just like the models with
continuous corners, where ours are joined by simple mechanical splicing with
wire nuts.

Out West we know of an installation using 80 foot towers that also uses wire
nuts for balanced feeder connections to antennas, and the owner does not
have maintenance problems; thus, it is even useful for longer than Field Day
type installations.
73, Stuart K5KVH