> Feeding a 1/2 or 1/8 wavelength antennae can be a bit more difficult
> as they will not be 50 ohms and possibly unbalanced.=20

Well, a 1/4 wave whip is not balanced either.

>This can lead to
> additional losses & so reduce the actual transmitted  and received
> power. This can be sorted out using baluns or transmission line stubs
> but would require suitable gear to fine tune & is likely to be more
> trouble than it's worth.

A better idea would probably be to use a 'rubber ducky' style coiled
wire if a 1/4 wave is too long physically. In a lot of cases a 1/4 wave
length of wire wound around a suitable diameter will do better than a
straight shorter aerial. It may require a bit of tweaking to get the
+/-j component tuned out, but with suitable test equipment that is easy
to do.

> A gain antenna (e.g a yagi) will give you longer range, but then
> again, may take a bit of setting up. If you know any hams you might be
> able to do some basic tests using simple gear (transmitter, receiver,
> VSWR meter) in the 70cm ham band. In NZ this is 430MHz - 440MHz (with
> some frequencies  reserved for satellite use) so includes the 434MHz
> frequency of interest.
>=20
> I am in the position at the moment of working with RF gear and have
> access to test equipment. I measured one of my Wifi antennas and found
> it was slightly off frequency. A small adjustment to make it resonant
> and the performance has improved significantly so I can vouch for the
> fact that resonance does make a difference.


--=20
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--=20
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