Finding a cable break in Husqvarna Automower robotic lawnmower boundary wire using a MW/AM radio

This is a tutorial, how to find cable breaks in Husqvarna Automower robotic lawnmower boundary or guide wire using a MW/AM radio, a multimeter and a car battery.
Boundary wire resistance:
smaller than 20 Ω - solid or blinking (ECO mode) green light illuminated by charging station LED;
20 - 50 Ω - solid blue light illuminated by charging station LED (only some models);
more than 50 Ω - blinking blue light illuminated by charging station LED.
Blinking yellow light is illuminated by charging station LED, when there is a brake in at least one of the guide wire (only some models).