An ATU aerial tuning unit for shortwave HF and end-fed aerials
If you can't see the video, please insert this title URL into your browser search box: https://www.youtube.com/watch?v=o43sAF4HwJs . This is post 2232 in a continuing series of simple ham radio antennas. End-fed half wave and random length antennas are great for portable and emergency operations, if they are matched to the impedance of your HF transceiver. In many cases a decent match will not be found without an antenna "tuner." According to W8JI, the impedance "can be 6850 ohms on 80 meters, decreasing to 1360 ohms on 10 meters." In this well-produced video, Ray of the "Radio Workshop" shows us a simple circuit that will match the high impedance of your long wire antenna to the relatively low impedance of your HF Transceiver. Ray offers these remarks: "How to construct an aerial tuning unit for use with end fed aerials, including inverted L antennas. A simple L-match ATU for the short wave amateur ham bands which is inexpensive a