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24 Apr
2012
24 Apr
'12
9:16 p.m.
any one have a good idea for a omni directional antenna for the birds?
3/4 wave vertical. Has almost 7 dBi gain above 30 deg. For 70cm downlinks, this means a 19.5" vertical over a ground plane. Also is a perfect 1/4wave on 2 meters.
It's the yellow curve on the plot about 80% down this page: http://aprs.org/astars.html
Bob, Wb4aPR
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