Vertically polarized antennas are used at lower frequencies where you
would need very high, huge masts for supporting horizontally polarised
antennas. Most of ShortWave antennas (commercial services) are
horizontally polarised as well (log periodics, rombics, etc). It is
matter of mechanical issues, as other guys already mentioned.
73 Mirko, S57AD
David Gilbert pravi:
> That's one good reason for it. Another is that in the case of only one
> yagi, mounting it vertically puts all the elements in line with the
> tower/mast, potentially causing unwanted electrical interactions.
>
> Another is that vertical elements (long at HF frequencies) would tend to
> interfere mechanically, assuming you wanted to rotate the antenna, with
> guy wires or any wire antennas (80m dipole, etc) hung from the top of
> the tower unless you used a really long mast.
>
> Another is that horizontally configured yagis for other bands (or phased
> for the same band) can easily be stacked one above the other on the same
> mast. Imagine mounting three vertically configured monoband yagis one
> above the other.
>
> 73,
> Dave AB7E
>
>
>
> On 7/2/2010 9:51 AM, Kelly Johnson wrote:
>
>> A co-worker asked me today why hams use horizontally polarized yagi's
>> instead of vertically polarized. Am I correct that it has to do with
>> ground reflection gain?
>>
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