The Collins Aerospace DF-500 Direction Finder is a state-of-the-art, software-defined radio system engineered to enhance the effectiveness of airborne search-and-rescue (SAR) missions. Covering a wide frequency range from 30 to 407 MHz, it supports all major distress signals including 121.5 MHz, 243 MHz, and COSPAS-SARSAT 406 MHz, along with ARGOS, AIS, and DSC protocols. Its omnidirectional, flush-mounted antenna ensures constant 360° scanning, while its multichannel architecture allows simultaneous monitoring of multiple frequencies. The DF-500 delivers rapid signal acquisition—under 300 milliseconds—and highly accurate bearings of less than 3°, enabling SAR teams to quickly locate beacons up to 116 nautical miles away, even identifying beacon GPS coordinates when available.