Which frequency range is not associated with low-frequency (LF) signals?

The frequency range that is not associated with low-frequency (LF) signals is correctly identified as the range of 300 kHz to 3 MHz. This range falls under the medium frequency (MF) category. Low-frequency signals typically range from 3 kHz to 30 kHz, which includes audio frequencies and early radio communications.

Understanding the classification of radio frequency bands helps clarify why this range is classified as medium frequency. LF signals are characterized by their ability to propagate over large distances, especially during the night when atmospheric conditions are favorable. In contrast, the 300 kHz to 3 MHz range is used for various applications, including AM radio broadcasting and navigation signals, but it does not fit into the low-frequency category which is strictly defined for lower ranges.