Vertical Whip Antennas And Gain Question ?
Hello,
Am a real novice when it comes to antenna theory, but am trying to learn.
if anyone could explain the following for me, even though I admit it's
really awfully basic, would be most appreciative.
Am interested in receiving only, around the Marine VHF bands of 156 MHz, or
so.
I understand that "Gain" is achieved in many antenna configurations by
making them very directional.
My understanding is that you in effect re-shape the lobes to be prominent
along one axis, and minimal at right angles.
So, how is Gain achieved in a
vertical whip (the specs usually mention 3 or even 6 db), or the
rubber-duckie, types of antennas used so often on handheld scanners (or
mounted to recreational boats) ? They are, I believe, truly omni
directional.
Also, are there vertical whip antennas that are directional, with "gain"
perhaps ?
Thanks,
Bob
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