Hello all.

I would like to try some portable HF operation this Summer, and am
considering trying some kind of a 75-ohm zip-cord dipole antenna.  My
portable set-up will consist of an Icom IC718 HF rig and an LDG AT11MP
auto-tuner.  I also have acquired a 4-1 balun to put in line between the
auto-tuner and the antenna.

My question is how to design the zip-cord antenna for maximum performance.

A ham friend has told me to calculate the length needed for the lowest
frequency I wish to operate on, unzip the wire to accommodate that length,
put a zip-tie where the split ends so it won't split any further, and just
use the remaining cord as my feed line.

Another friend is somewhat more specific.  He suggests that I should measure
out 22 feet of wire, unzip it, and use 28 feet as the feed line.  (In other
words, a 50-foot roll would be needed for this design.)

The minimum frequency I wish to operate on would be 3.5 mhz.

I also would like to be able to operate especially on 40 and 20 meters.

Does anyone know if one or both of these designs would work?

Also, how do you support such an antenna, both at the center and on the
ends?

I am in the process of acquiring some insulators for this latter purpose,
but out here in the boondocks of Central Michigan, those are sometimes hard
to come by.

Any help here, or any other suggestions for zip-cord antenna designs, would
be appreciated.

This whole area of portable HF operation is new to me, but since I recently
have been appointed as EC/RO for our county, I feel the need to give it a
try.

Thanks much.

Best 73 from Tom Behler:  KB8TYJ