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How to Make a 450 Ohm Ladder Line

450 ohm ladder line provides a better match to the typical balanced antenna (such as a dipole or Yagi array) than coaxial cable. Not only is coax an unbalanced feedline, it also inherently has a low impedance of 50 to 75 ohms. Throughout the history of amateur radio, hams have made their own twin-lead ladder line at home. The basic nature of radio signals has not changed and it is just as viable to make your own 450 ohm ladder line today as it was in the 1920s.

Things You'll Need

Solid wire, 14 AWG uninsulated copper-clad, twice as long as your desired line length
Wire cutter
Bench vise
Dowels, 5/16-inch hardwood
Ruler
Permanent marker
Wood-cutting bandsaw
Drill press with vise and 1/8-inch bit
Super glue
Epoxy with hardener
Mixing cup
Paintbrush

Instructions

- 1
  Cut the wire in the center to form two equal-length sections. Clamp one end of each wire into the bench vise, spaced 1.5 inches apart.
- 2
  Cut the dowels into 2-inch sections on the bandsaw. These will be the spacers. Cut enough to equal one spacer per foot of the original (uncut) wire length.
- 3
  Drill a 1/8-inch hole through each spacer, 1/4 inch from each end.
- 4
  Slide the spacers onto the wires; one wire through each hole. Position them so there is a spacer every 6 inches along the wires. Put a drop of glue on each hole of the spacers to hold them in position on the wires.
- 5
  Mix the epoxy according to the directions on the label. Paint each spacer on both sides with the epoxy.

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