FM Strong Signal Capture and AM Overloading

FM capture is an unusual condition that occurs when traveling in the vicinity of a broadcast tower. If listening to a weak FM station when passing the broadcast tower, a stronger station may interfere without changing the radio chassis. When passing the tower, the station may switch back and forth a few times before returning to the station originally tuned. When several broadcast towers are present (common in metropolitan areas) several stations may overload the radio chassis, resulting in considerable station changing, mixing, and distortion. Fortunately, this condition is localized and it will not harm the radio chassis. Some overloading may also be noticed on AM, but usually to a lesser degree.