HF Antennas & Feeder Lengths in Metres

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This handy chart was developed by Gary, ZL2IFB. It is a very simple way of finding out what length of wire you need for your particular frequency. Thanks Gary!

Band CW SSB ¼ wave ¼ – 5% ¼ x 0.66 ½ wave ½ – 5% ½ x 0.66 Full wave F – 5% F + 10% F x 0.66
160m 1.825 41.07 39.01 27.38 82.13 78.03 54.76 164.27 156.06 180.70 109.51
1.850 40.51 38.49 27.01 81.02 76.97 54.02 162.05 153.95 178.25 108.03
80m 3.520 21.29 20.23 14.19 42.58 40.45 28.39 85.17 80.91 93.69 56.78
3.800 19.72 18.74 13.15 39.45 37.47 26.30 78.89 74.95 86.78 52.60
40m 7.025 10.67 10.14 7.11 21.34 20.27 14.23 42.68 40.54 46.94 28.45
7.100 10.56 10.03 7.04 21.11 20.06 14.07 42.22 40.11 46.45 28.15
30m 10.105 7.42 7.05 4.94 14.83 14.09 9.89 29.67 28.18 32.63 19.78
20m 14.020 5.35 5.08 3.56 10.69 10.16 7.13 21.38 20.31 23.52 14.26
14.250 5.26 5.00 3.51 10.52 9.99 7.01 21.04 19.99 23.14 14.03
17m 18.075 4.15 3.94 2.76 8.29 7.88 5.53 16.59 15.76 18.24 11.06
18.120 4.14 3.93 2.76 8.27 7.86 5.51 16.54 15.72 18.20 11.03
15m 21.020 3.57 3.39 2.38 7.13 6.77 4.75 14.26 13.55 15.69 9.51
21.250 3.53 3.35 2.35 7.05 6.70 4.70 14.11 13.40 15.52 9.41
12m 24.900 3.01 2.86 2.01 6.02 5.72 4.01 12.04 11.44 13.24 8.03
24.950 3.00 2.85 2.00 6.01 5.71 4.01 12.02 11.41 13.22 8.01
10m 28.025 2.67 2.54 1.78 5.35 5.08 3.57 10.70 10.16 11.77 7.13
28.500 2.63 2.50 1.75 5.26 5.00 3.51 10.52 9.99 11.57 7.01
6m 50.100 1.50 1.42 1.00 2.99 2.84 1.99 5.98 5.68 6.58 3.99
52.050 1.44 1.37 0.96 2.88 2.74 1.92 5.76 5.47 6.34 3.84

Where a full wave in metres = frequency in Hz divided by the speed of light (299,792,458 m/s)

Reduce dipoles by ~5% for end effects. Add 5-10% to full wave loops. Trim all antennas to resonance.

Lose one third physical length for velocity factor of typical coax. 73 de ZL2iFB