Larkspur is a city of 12,000 residents, 10 miles north of the Golden Gate Bridge in Marin County, California. Long before Golden Gate Bridge was built an enterprising group of volunteer firemen started an outdoor dance called the Rose Bowl. The Saturday night summer dances started in 1913, and soon became a Bay Area institution that ran for fifty years. By the 1920s, due to profits from the Rose Bowl Dance, the Larkspur Volunteer Fire Department had a solid financial base. The department without any government funding created one of the finest equipped small town fire departments in the United States.

Over the next decade the department purchased state of the art fire engines, built a new fire station, installed a Gamewell Fire Alarm System and a Gamewell Type B Diaphone. The West Coast was new frontier for Gamewell Diaphone. This diaphone was one of the first installed in California. Seventy plus years later this diaphone still operates and may be the West Coast's longest active diaphone in continual operation.

What makes this diaphone unique is simple - it has never been touched. It operates with much of the original equipment from the auxiliary tank to the tip of the cone. The low voltage system has continuously energized the control valve and not a single bolt or nut has ever been adjusted to the diaphone assembly itself. In all that time it just works. The diaphone was mounted on a custom built tower seventy feet above the old firehouse that was located at that time in the basement of Larkspur City Hall.

In the 1940s, the Larkspur Fire Department was featured on the cover of "Colliers" magazine and the Larkspur Fire Station and diaphone were featured in the motion picture "Impact". In the film one can get a quick look at the diaphone, the 1939 Fire Station and the American LaFrance engine driven by Fire Chief John Raggio. The Gamewell Box Alarm System was monitored at the fire station. When a box alarm was pulled the diaphone was activated and sounded the number corresponding to the box number. In the film it happened to be Box 13. The Gamewell Diaphone and Box Alarm System continued to operate for the next forty years.

Click button for sound.

By 1980, the 911 Emergency Telephone System had eliminated the need for the fire alarm box type system. But Larkspur’s Greenwell Diaphone continues in its role as a back up system. The "Blast" of the diaphone can be heard seven miles away and is famous for startling people who are in the area during its daily 12 noon and 5 pm activation.

The diaphone operates off a six-volt system and is tied into a Simplex clock. The two supply tanks and industrial compressor provide an overabundance of compressed air through a 1½ inch copper supply line. The pressure is reduced at the auxiliary tank high in the tower and fed to the Diaphone through a 3/4 inch copper pipe. A honeybee hive occasionally inhabits the top of the tower right next to the diaphone itself. Next door is the Larkspur Fire Station and one can find the Larkspur Fire Department’s History Room featuring the original Gamewell catalogs, equipment and box alarms.

In this era of high tech digital data, thermal imagers and laser surgery it is fascinating that the Larkspur Fire Department’s Gamewell Diaphone remains a classic example of mechanical reliability and simplicity that is still operates on a daily basis.

Click here to view interactive slide show of Diaphone