What is the frequency range of an aircraft's Automatic Direction Finding (ADF) equipment?

The correct frequency range for an aircraft's Automatic Direction Finding (ADF) equipment is from 190 kHz to 1750 kHz. This range encompasses both the upper and lower frequency limits used for NDB (Non-Directional Beacon) signals, which are essential for ADF operations in navigating aircraft. ADF systems utilize these frequencies to determine the direction to the station broadcasting the navigation signal, which aids pilots in navigating and maintaining their course.

Understanding this specific range is crucial, as it reflects the operational frequencies for ADF systems, differentiating them from other communication equipment that may operate at different frequency bands. The design of ADF equipment to function effectively within this range ensures that pilots have reliable tools for navigation in various weather conditions and over significant distances, enhancing flight safety and operational efficiency.