[Elecraft] Feeding the Halfwave Ant

[Stuart Rohre]

My 49 years of antenna useage has taught me it is bad to bring the high 
voltage end of the antenna down close to the earth because of ground losses 
due to the capacity of the antenna to earth.  Not to mention the high RF 
voltage induced into the shack.

My center fed antennas have all worked much better than my end fed antennas, 
all the way from end fed quarter wave to a 400 foot long end fed long wire. 
Those two were the worst, and were possibly aggravated by being used over 
very poor earth as to RF conductivity.

If you could keep the end of an end fed antenna up high, or put the LC 
network up at the end of a high wire, and run coax to the rig, you could 
avoid the bad effects of bringing the fed point "into the shack".

You could also end feed the wire with balanced line in the Zepp feed 
arrangement.  Current unbalance there is only 10 per cent per L. B. Cebik's 
modeling. (W4RNL's antenna site www.cebik.com)

For a field portable center fed half wave horizontal, you do not absolutely 
have to use a balanced tuner, or even a heavy balun!   You can use a one to 
one cable bead choke on the end of an L net tuner.  Minimal inductor loss, 
(only one), and one C.  Use of correct length of feeder with such a tuner, 
brings the impedance within range of the tuner.  Or use the bead choke on 
the output of a conventional Tee tuner.

Stuart
K5KVH