[Antennas] gain vertical

[fkamp at comcast.net]

I just built and installed a vertical collinear for 2 meters.  Two half
waves.

It is touted to be an omnidirectional gain antenna.  This thing works
well.  Much better than the 1/4 wave ground plane I was using at the
same elevation.

Then I got to wondering.  I understand how a beam works.  You get gain
in one direction because the signal is 'directed' toward the favored
direction.

I am not sure where the gain comes from in a vertical gain antenna.  It
is still omnidirectional.  Seems the only thing it plays with is
take-off angle.  I dont see how that translates to gain.

Regards,
Frank Kamp
K5DKZ