On Sunday, October 28, 2012 6:18:58 PM UTC-5, Channel Jumper wrote:
But your dipole antenna needs to be resonant - 1/2 wavelength on the
lowest frequency you desire to operate on.

Like the G5RV that you dislike, if one removed the feedline from a 1/2WL resonant center-fed dipole, it is no longer resonant. Resonance implies a low resistive feedpoint impedance. The G5RV antenna system has a low resistive impedance looking into the series matching section on 75m, 40m, and 20m (also on 12m).

3/2WL dipole + 1/2WL feedline = resonance on 20m

3/4WL dipole + 1/4WL feedline = resonance on 40m

3/8WL dipole + 1/8WL feedline = resonance on 75m.

The (G5RV) ladder line is the matching network and it only works on 20 meters.

Here's technical proof that it also works on 75m and 40m.

http://www.w5dxp.com/G5RV.HTM

The Smith Chart SWR arc indicates how series section transformers really work. The G5RV is a reasonably good antenna on 75m, 40m, 20m, and 12m. Not so good on 15m and not good at all on 30m, 17m, and 10m. A ZS6BKW is a better choice to obtain 17m and 10m but one loses 75m.

The G5RV antenna system is what it is. It is neither a gift from Heaven nor a design straight from Hell.
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73, Cecil, w5dxp.com