Radio waves radiate more or less in all directions from an AM tower, meaning
that some of them radiate skyward.


An ideal non-directional radiator which is 180 degrees or shorter has no
radiation at 90 degrees to the horizontal plane.

The taller a radiator is, over 180 degrees and up to 225 degrees, the higher
the radiation is in the horizontal plane, and the less the radiation is in the
vertical plane except for 90 degrees, where the radiation increases above 180
degrees to reach a maximum at 360 degrees.

A 360 degree radiator which is center fed and has the base grounded through a
capacitance is called a Franklin, and is the most efficient radiator known.
This is essentially two colocated 180 degree radiators.