[Antennas] Open wire transmission line

[PaulKB8N at aol.com]

I've built open feeders for years using PVC or Teflon coated wire that I  
bought at swapmeets by the spool and for a song.  If you find #16 to #18  coated 
wire, it will generally work very well.  I always carry a VOM and  test the 
wire for resistance.  Generally I find a good quality spool of  wire has less 
than 10 ohms of resistance per 1000 ft.
 
For spacers, I've found circuit board slide mounts to be excellent.  A  local 
electronics store sells them for ten cents each for a 6" U-shaped mount  that 
appears to have great dielectric properties.  I cut them in half and  drill 
drill a hole big enough that the wire fits through snugly.  I put a  spacer at 
between four and five times the spacing between the wires, if the  spacing is 
4", ideally the distance between spacers is 16" to 20", although for  long 
horizontal ru
ns you can often exceed that distance.
 
Another great alternative is to use #18 solid enamelled copper magnet  wire.  
I did a search on the web and found several places selling it by the  pound 
(it ends out being about five cents a foot).  With this wire and some  homebrew 
spacers, you can emulate the old sexton stuff.
 
I've also had pretty good success with plastic coat hangers as spacer  
material.  You can buy them cheap at WallMart (I once got 20 for $.88) and,  if the 
microwave test is any indication, they have good dielectric  properties.
 
Hope this is of some help.
 
Paul, K5AF
 
Paul  Schaffenberger