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108 decibels to ward off boat burglars

Couple's invention is simple: disconnect the shore power, and would-be thieves get a deafening blast

After nearly losing their boat to intruders three times, Walter and Joanne Dethier decided to fight back. With the help of a friend in the boat business, they invented a theft-deterrent system that's so simple it's amazing no one had thought of it before.

Adversity was the mother of invention for the Dethiers, who developed the theft alarm after nearly losing their boat three times.

Disconnect the boat's shore power, and the Dethiers' patented POGO Alarm triggers a 108-decibel horn blast that sends intruders running for cover. "You can't steal a boat without disconnecting the power," says Walter Dethier.

When thieves pull the plug to the shore power, the alarm is so loud and so unnerving they aren't going to hang around and try to figure out where the noise is coming from, says Dethier. "It's a very simple concept."

And that's its beauty. Plug the 110-volt power cord from the alarm's nondescript black box into a 110 outlet on the boat and the box's other cord - a 12-volt connector - into the cigarette lighter or hard-wire it directly to the battery. A third wire running from the back of the box has a doughnut-sized horn at the end. You can hide the horn. The black box looks like just another piece of electronic gear.

"It's plug-and-play," says Dethier. "There's no fancy technology, no tools."

Loss of shore power triggers the battery-powered horn. About the size of a CD player, the black box houses a 1.5-amp battery maintainer that keeps the boat's battery charged so it's always up to the job of powering the horn.

The Dethiers, of Warren, Conn., went to friend Christopher Cestaro, owner of Ocean Performance, a high-performance-boat dealership in Old Saybrook, Conn., with an odd request: Could he build an alarm to alert them if someone unplugged their shore power and tried to take their boat while they were sleeping below?

The couple had their reasons for asking.

One night in November 2008, Walter Dethier chased off five black-clad figures - a boat repo team, as it turned out - who tried to make off with their Magnum 40 from a dock in the Florida Keys while Dethier was sleeping below and his wife was watching television. Loss of power to the television and the thump of unplugged shore power cables thrown on deck alerted them that something was awry. The team had misidentified the Dethiers' boat as the one they were repossessing.

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Later that winter, they again were sleeping down below at night when Walter Dethier heard the air conditioner cycle down. This time he found a drunk in the cockpit trying to make off with their Magnum. Dethier, armed this time, held the thief at bay until police arrived. In January 2009, the couple were home in Connecticut when the dockmaster at the Keys marina called. Again, the repo team - still unpersuaded they had the wrong boat - grabbed the Magnum and motored to the ocean. The Coast Guard, alerted to the heist, intercepted boat and crew and escorted them back. The Dethiers have sued in U.S. district court in Connecticut, seeking more than $75,000 in damages from the repo firm.

Joanne Dethier says the episodes so upset her that she was afraid to sleep on the boat. Cestaro, an assistant chief of the Old Saybrook volunteer fire department, had done work on sirens for the fire department. He figured he could devise something for the

Dethiers. "It took a couple of weeks," he says. "I sent it to them. They put it in their boat, and Joanne was happy."

Finding nothing like it on the market, they refined and patented the system and now have started selling it ( They exhibited at the Atlantic City (N.J.) International Power Boat Show in early February, and later in the month showed it around the Miami International Boat Show, where it caught the eye of Bill Golden, president of Golden Boat Lifts, of Fort Myers, Fla.

"We're telling everybody about it," Golden says. "The only alternative I have [for lift customers] costs $3,500 plus an electrician, and it still can be bypassed. For the cost, Walter has got the best thing going." The POGO alarm costs just under $500.

Golden says boat theft has reached epidemic proportions in Florida and the Caribbean as smugglers have taken to stealing boats from docks and off lifts for use in transporting illegal immigrants. Thieves recently cut both cables of a Golden boat lift behind a home in Jolly's Harbour, Antigua, slid a 46-foot Sea Ray worth about $500,000 off the lift and towed it to the ocean unnoticed while security guards were on duty.

"Now that's pretty brazen," Golden says.

Golden says his boat-lift customers can install the alarm in their boats or on the lift with the 110-volt power cable wrapped around a railing on the boat so the thieves have to unplug the cord to lower the lift. Then all hell breaks loose.

"They're going to leave and find another boat," Golden says.

Walter Dethier says POGO, an acronym for "Power Off, Game On," can be used as a theft deterrent for boats, personal watercraft, recreational vehicles, cars, campers, airplanes and heavy machinery.

"We've had a tremendous response from landscape contractors," Dethier says. "It was our life experience that gave birth to this. And it was Chris' understanding of technology that made it a reality."

For information visit or call (860) 391-5409.

This article originally appeared in the May 2010 issue.