The U.S. Coast Guard Navigation Center issued a special notice reminding mariners that any vessel operating in U.S. waters equipped with an Automatic Identification System (AIS) should confirm that the proper channel frequency has been selected. The standard default AIS frequency is 161.975 MHz (AIS1 or channel 87B). The alternate AIS frequency is 162.025 MHz (AIS2 or channel 88B). These frequencies can be verified through the manufacturer’s operation/owner’s manual for the AIS installed. (8/23/10).
(Source: Bryant’s Maritime News)