ELLSWORTH, Maine — Mariners who want to keep emergency signal beacons beyond the end of the month should make sure they are digital devices and not analog, according to a Coast Guard official.

That’s because the Coast Guard will stop listening for analog emergency position indicating radio beacons signals, or EPIRBs, after Jan. 31. As of Feb. 1, satellites that track such devices will be programmed to detect digital signals only, according to Lt. Lisa Tinker of U.S. Coast Guard Sector Northern New England in South Portland.

The reason for this is the better technology offered by digital EPIRBs, Tinker said Tuesday. She said the Coast Guard has been working to make sure mariners and aviators in Maine and nationwide are aware of the pending switch in technologies.

“[The difference between] having an analog and digital beacon can mean the difference between life and death,” Tinker said.

Satellites that track such signals can be much more precise in determining where a digital EPIRB signal is coming from than they can be with analog signals, Tinker said. Analog EPIRB signals can result in search areas as large as 500 square miles, but digital EPIRB signals can be narrowed down to 25 square miles. If the digital EPIRB is equipped with a global position system, she said, its location can be narrowed to within 100 yards.

Tinker said satellites couldn’t discern between analog beacons and similar analog signals emitted by other types of electronic devices, which has resulted in a high rate of false alarms. Devices that have been confused with triggered EPIRBs include automated teller machines, stadium scoreboards and even microwave ovens, she said. As a result, a signal that could be interpreted as being a triggered analog EPIRB three miles out at sea could end up just being a microwave oven at an oceanfront restaurant.

“A lot of times, you can get false alerts from [analog beacons],” Tinker said.

Such unnecessary searches can waste thousands of dollars of taxpayer money, divert rescue personnel from actual emergencies, and put lives at risk, she said.

Digital EPIRBs also can be programmed to relay information about the person to whom the beacon is registered. This also will reduce unnecessary searches because responding agencies will be able to contact the registered owner to find out if there really is an emergency, Tinker said. Even if they cannot contact the registered owner, they will be able to tell who and perhaps which vessel or aircraft they should be looking for.

The EPIRBs that are being phased out include those that transmit on 121.5 or 243 MHz analog frequencies. Starting Feb. 1, rescue response agencies such as the Coast Guard will receive distress signals broadcast from digital EPIRBS at 406 MHz, according to a Coast Guard press release.

EPIRB owners are required to register their digital beacons with the National Oceanic and Atmospheric Administration and to make sure the ownership contact information is up-to-date, even if they buy used beacons. They can be registered on the Internet at www.beaconregistration.noaa.gov/ or by calling 888-212-SAVE.

Bill Trotter

A news reporter in coastal Maine for more than 20 years, Bill Trotter writes about how the Atlantic Ocean and the state's iconic coastline help to shape the lives of coastal Maine residents and visitors....