By Ron Schwiesow
odern VHF marine radios include Digital Selective Calling, a semiautomated method of making radio calls. DSC allows mariners to send instant, digitally coded distress calls to the U.S. Coast Guard and other vessels within transmission range. It also allows selective, digital communication with other DSC-equipped vessels. When a GPS receiver is connected to the VHF radio, your vessel’s location is automatically included in the transmissions—distress or otherwise.