Local Radio v1.15.0 for American Truck Simulator game.
How the system works:
Every city acts as a transmission tower with a certain range, and every city is bound to a country.
The program check the distance to every city, and when it is within reach, the stations for that country are displayed.
When a city from a different country is closer than the one currently connected to (with a treshold),
the radio automatically switches to that country.
What does that coverage map show?
It shows all the transmission towers (the cities), with a range circle.
The black inner ring is the clear audio border (~20% static). Each country has its own (random) colour,
to make it easier to see the difference between them.
Tested on game version 1.6.x