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Old 17-Jan-2012, 6:47 AM   #11
GroundUrMast
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Join Date: Oct 2010
Location: Greater Seattle Area
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For a vehicle in motion or frequently moved then parked in various locations and facing a random direction, you'll need an antenna that has fairly equal reception from all directions.

As I mentioned in post #2 of this thread, 'gain omnis' such as collinear and 5/8 wave verticals achieve gain by focusing on the horizon more than the shorter and simpler 1/4 wave over ground plane vertical antenna. Both the collinear and 5/8 wave designs incorporate some type of impedance matching network so they can efficiently couple received energy into the feed line. Simply making the antenna element longer will detune the antenna leaving you with less signal to the radio.

Most of the fractal antenna designs I've seen tend to be somewhat directional. Those designs would provide gain in one or two directions and less gain in the other directions. However, if you can provide a link to one or more fractal designs, I'd be happy to look them over for you.
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If the well is dry and you don't see rain on the horizon, you'll need to dig the hole deeper. (If the antenna can't get the job done, an amp won't fix it.)

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Last edited by GroundUrMast; 17-Jan-2012 at 9:21 AM. Reason: Sp.
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