Dipole Antenna for the 50-MHz Band

Dipole Antenna for the 50-MHz Band

By: Igor Grigorov, VA3ZNW

Every radio amateur wants fill up any free space by an antenna. Not nearly enough antennas! So as I found a free space where I can install an antenna. True, it was a small place where I could install a small antenna. I choose a dipole antenna for 6 meter Band. It was because the diagram of directivity of the new antenna will be seen to line East- West. My old 6 meter dipole antenna had the diagram of directivity that seen to line South- North.

Of course, a simple dipole antenna is not a big gun. However, as I noticed in practice, the direction of even such simple antenna plays the role. The ham radio stations on the 6 meter Band, which were heard by me enough loud, all of them lay on the line South- North.

Another reason was the coming ARRL September VHF Contest. At the last ARRL Spring VHF Contest almost all stations in my log were from the line South- North. I hope add the line East- West at the coming contest. In general, the design of a dipole antenna is very simple. Figure 1 shows a dipole antenna for 6 meter Band.

But the simplicity is only on the picture. In practice, it is necessary to make a central insulator, it is necessary to take into account the length of the wire in the center and ends insulators, it is necessary to take into account the shortening factor of the wire in the plastic insulation that was used for the antenna.

For the central insulator I decided to use a nylon dog bone insulator. Figure 2 shows the insulator and SO- 239 connector. In the middle of the insulator I cut a square place for installation of the SO- 239 connector. In the center of the insulator it was made hole for wire going to the center wire of the SO- 239 connector. The connector was fixed to the insulator with help of two screws. Holes for the screw were drilled in the insulator. Figure 3 shows the SO- 239 connector mounted on the insulator and the antenna wire connected to the SO- 239 connector. The holes and places where the connector mounted on the insulator were protected with weather proof automotive epoxy (I have bought the epoxy several years ago in Canadian Tire store). I used Egg insulators for ends of the antenna. Figure 4 shows these isolators at the end of the antenna.

Figure 1 Dipole Antenna for 6- meter Band

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