K1YW wrote:
"Artsci takes into account:
To properly estimate a signal`s range, you must have a few important
figures----

Frequency / Band
Transmitter power (in watts)
Antenna height (from sea level)
Antenna gain (net after coax loss)

As a practical matter, first you must have a line-of-sight path. Then
you can worry about path attenuation, gains, losses, transmitter power
and receiver sensitivity.

Attenuation between stations with an obstructed path (including earth
bulge) rises so rapidly with the obstruction that non of the other
factors matters except in the case of brute force communication, such as
atmospheric scatter.

Best regards, Richard Harrison, KB5WZI