David wrote:

When one says 50' ''high'', I take it they mean ''above'' the average surroundings.

You assume too much. Most times when someone describes their antenna
height as "35 feet above ground" they mean 35 feet above the ground in
their back yard.

How high is your antenna? Have you calculated it's height above average
terrain (HAAT)?

The typical listener has excellent equipment as long as they have a car radio.

Not with the typical car antenna a few feet above ground, and alongside
an 18 wheeler.

Art H.