The rhombic antenna is also a wide band aerial that may cover, of
course with different performances, several bands.
Unidirectionality and (some) constant impedance are also obtained
terminating the antenna in a dummy load, a load that needs to be
proportioned to the used power because about half of the delivered
power is not radiated but just dissipated there.
Unless the space and the peculiar environment required to install a big
rhombic (several wavelenghts of space and supporting towers to allow
the correct tilt) is already available, a yagi or a phased array can
offer a bigger gain in a much smaller size and area.
73,
Mauri I4JMY
> Hi Jack,
>
> > Which has more gain.
> >
> > Jack
>
> A large Rhombic has more gain than a small beam.
>
> A large beam has more gain than a small Rhombic.
>
> For a given amount of space, a properly built "beam" will always
> have MUCH more gain than a Rhombic.
>
> For a given beamwidth of the main lobe, the beam will have more
> gain than a Rhombic.
>
>
>
>
> 73, Tom W8JI
> w8ji@contesting.com
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