Radio Direction Finding - ELT and Project Lifesaver
Radio direction finding is the use of receiving equipment and directional antennas to locate a signal source. Cowlitz County ARES®/RACES has been involved with finding Emergency Locator Transmitters for a number of years. These devices are used on general aviation aircraft and boats (called EPIRB in marine use) as automatically activated distress beacons. Specialized equipment is used to triangulate a position on the ground when the activated signal is detected. Periodic drills are held with a test transmitter so teams can practice their skills.
Our radio direction finding role is in the initial stages of being expanded to include assisting Cowlitz County Search and Rescue in tracking Project Lifesaver beacons worn by Alzheimer's patients. CCSAR, also sponsored by the Sheriff's Office, has taken the lead in providing this service to Alzheimer's patients locally. Patients wear a small (wristwatch size) beacon that continuously transmits a beeping signal. Alzheimer's patients are prone to wandering off so if a patient goes missing teams can quickly conduct an organized search starting from the last known location. The same direction finding techniques used in ELT searches can be used in Project Lifesaver.