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Old September 15th 04, 10:19 AM
Matt
 
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"Donald K" wrote in message
...
Mac Tabak wrote:

I know a few have suggested discones....but they are really for
horizontalradiation, you need vertical polarisation for police.
Try a 1/2 wave dipole, easy to make.


Um, discone *is* vertical.

Page 7-29 ARRL Antenna Book, 20th Ed.
--
"One ought, every day at least, to hear a little song, read a good poem,
see a fine picture, and, if it were possible, to speak a few reasonable
words." - Johann Wolfgang von Goethe


Yep, I sense a little bit of confusion entering the eqation here. The
Discone is vertically polarised, whereas typically a dipole is horizontally
polarised - particularly on the lower frequencies. For example on 80m (3.5
MHz), a dipole would typically be around 20 metres in length, which is not
the easiest antenna to string upright, so most poeple will put them up
horizontally. On the VHF and UHF bands, a dipole can be setup for either
vertical or horizontal polarisation and as stated a couple of postings
above, they are pretty easy to construct.




Matt