West Hudson Amateur Radio Club members got together at American Legion Post 99 to build their own multi-band end fed half-wave (EFHW) antennas. The EFHW is a half-wavelength antenna with the coaxial cable for your transceiver attached at one end. It has become popular with portable operators because it’s very simple in its construction and deployment. This antenna, which works on 10, 15, 20, and 40 meters, has a very high impedance of around 2,500 Ohms. It’s a good portable antenna that can handle up to 250 watts of power.
Starting from a kit obtained from the ARRL and made by HF Kits, each member planned, measured and drilled the box for the 49:1 impedence transformer. They then constructed the transformer by completing the appropriate windings around an FT240-43 toroid core and attaching it to a mounting board.
Finally, connections were soldered and a 100 pF capacitor was placed into the circuit to improve performance in the 10 and 15 meter bands.
Everyone had a great time. Three members built their own antennas and we built one antenna for the Club to keep for Club use or to loan out to members.