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How to Construct a Dipole Antenna

Whether you are a short-wave listener or a ham-radio enthusiast you will greatly enhance your hobby by constructing your own dipole antenna. The design is easy, the construction is relatively simple and the results are terrific. For many beginning radio enthusiasts who also like to "homebrew," or build their own equipment, the dipole antenna is a doable first project.

Things You'll Need

Wire
End insulators
Middle insulator
Feedline
Nylon cord

Instructions

- 1
  Decide on a primary frequency that you want your antenna to be built for. Generally, antenna builders choose a middle frequency of the particular radio band that they frequent.
- 2
  Calculate the length of your half-wave dipole antenna. Use the formula L=468/MHz which will calculate the antenna's length, L, in feet. Substitute the megahertz number of the desired frequency for MHz in the formula.
- 3
  Add 12 inches to the calculated length of the antenna. This will be used to trim the antenna and to connect it to the end connectors that will attach the antenna to the two antenna supports.
- 4
  Cut the wire into two equal halves and connect one end of each wire to the center insulator. Connect the other ends of both wires to individual end insulators and tie each insulator to nylon cord.
- 5
  Attach the feedline to the center insulator and solder each of its two conductors to one of the antenna's wires.
- 6
  Hoist the completed antenna onto its two supports with the nylon cord and connect the loose end of the feedline to your antenna tuner or to your radio.
- 7
  If you are going to use an antenna tuner, you are finished. If you are not going to use an antenna tuner, transmit on low power and read the antenna's efficiency on a watt meter or a standing wave ratio (SWR) meter. Lower the antenna, trim off a small piece off each end and retest the antenna by transmitting on low power. Continue to test and trim until the meter indicates highest efficiency.

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