NEWThe International Cospas-Sarsat System will cease satellite processing of 121.5/243 MHz beacons from 1 February 2009. All beacon owners and users should begin taking steps to replace their 121.5/243 MHz beacons with 406 MHz beacons as soon as possible. A good time to consider purchasing a 406 MHz beacon is when the battery on your 121.5/243 MHz beacon needs replacing. Typically, batteries need replacing about every five years. The sooner you upgrade, the better the service that the Cospas-Sarsat System can provide you if your beacon is activated in a distress event. Beginning in 2009, only 406 MHz beacons will be detected by the Cospas-Sarsat satellite system. This affects all maritime beacons (EPIRBs), all aviation beacons (ELTs) and all personal beacons (PLBs). However, other devices (such as man overboard systems and homing transmitters) that operate at 121.5 MHz and do not rely on satellite detection will not be affected by the phase-out of satellite processing at 121.5 MHz.