As many have alluded to here, height is might.
In November of 1974, I escorted a Mr. Oscar Seven (that was the name on his airline ticket) to California where he took a ONE WATT wideband frequency translator and installed it place 912 miles above the surface of the earth.
When Oscar is in full sun, anyone with the proper equipment and license can use it as long as they are within a 2500 mile radius circle centered on the point directly below Oscar VII. That means: two suitably equipped people, 5000 miles apart, can communicate with each other.
