Dipole Antenna for the 50-MHz Band

Figure 2 Dog Bone Insulator with SO- 239 Connector

Figure 3 Connector Mounted on Dog Bone Insulator and Antenna Wire Connected to SO- 239 Connector

Figure 4 Egg Insulator at the End of the Antenna

Let's discuss the practical implementation of the antenna. Before tuning, each side of the dipole had 160 centimeters of wire. The antenna was installed at height of 2 meters above the ground for the tuning. By symmetrically shortening the sides of the antenna, this antenna was tuned to minimum SWR at the frequency of 50.1- MHz. The SWR and input impedance was measured by MFJ- 259B. The device was connected directly to the antenna. At the resonant frequency of 50.1- MHz the antenna had input impedance of 75- Ohm that is the theoretical one. Figure 5 shows the final dimensions of the antenna tuned to 50.1- MHz.

Connection of the feeding coaxial cable to the SO- 239 connector was protected with Coax-Seal tape. A 100 feet long RG- 8 coaxial cable was used to run from the antenna to transceiver. Figure 6 shows the center insulator with connected feeding coaxial cable. The antenna was installed in a sloping position, the lower end of the antenna was at the height of 2 meters from the ground the upper end of the antenna was at the height of 4 meters from the ground. Figure 7 shows the antenna at its location.

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