>I don't know if this is relevant to your app, but a 1/4 wave radiates a
>significant amount of energy straight up. (along the long axis)  A 5/8 wave
>flattens this out.

>Depends on wether talking to spacecraft is what you're into :)

I agree with this, the lower angle of radiation is of benefit to ground
communication. A 5/8 wavelength whip also has another advantage, in that
it's resistive component of the impedance is very close to 50 ohms, and so
you need to only tune out the reactive part of the impedance, although this
is a larger reactive impedance than a quarter wave whip. At the end of the
day it can be a simpler aerial to use.

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