"Cecil Moore"
For a 1/2WL resonant dipole the feedpoint impedance is low:
R = (|Vfor|-|Vref|)/(|Ifor|+|Iref|) ~ 73 ohms
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The 73 ohm radiation resistance value applies to a physical 1/2-wave,
thin-wire, linear dipole in free space, however a reactance term of + j42.5
ohms also applies to such a configuration (Kraus 3rd Edition, p. 182).
The dipole length needs to be shorted by several percent in order to zero
out the reactance term, at which time (according to Kraus), the resistance
term will be about 65 ohms.
RF
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