[TowerTalk] baloon supported wire verticals

[Chuck Counselman]

At 9:35 AM -0500 4/4/03, Jerry Connelly wrote:
>...has anyone tried using two balloons with a dipole strung between them?

No; but, if I did, I would minimize the weight of the feedline by 
Zepp and/or Windom feeding.  Zepp feed uses a two-parallel-wire 
feedline, one-quarter-wave long, with one wire connected to the end 
of a half-wavelength antenna wire and the other feed wire floating. 
Windom feed uses a single-wire feedline connected to a 
half-wavelength antenna wire off-center.  At the transmitter end, the 
single wire is driven against "ground."

Zepp-Windom feed uses a two-parallel-wire feedline, one-quarter-wave 
long, with one wire connected to the half-wavelength antenna wire at 
the 60% point, and the other feed wire floating.  The input impedance 
at the transmitter end of the two-parallel-wire feedline is 50 ohms, 
and no additional balun is required.  A very excellent antenna, which 
I have used in the field, for QRP DX.

I'd make the two-parallel-wire feedline of thin Litz wire, with 
sections of plastic drinking straws for spacers.

73 de Chuck, W1HIS