The merchant vessel China Mountain, sailing under the Hong Kong flag somewhere off the South American coast, received the following message from Point Reyes this week along with the usual weather and traffic updates:

Important notice to Mariners: Please note: Effective 30 June 97, the call letters and frequencies of stations KPH and WCC will be assigned to the facilities of Globe Wireless. After many years of continuous service from our headquarters at Bolinas, Marshall/Point Reyes, and Chatham, the employees of KPH and WCC wish you fair winds and Bon Voyage.

So ends an 83-year chapter in West Marin history, spanning the birth of wireless radio to the predominance of global communications satellites. Marine Radio Station KPH, a fixture in the area since 1914, has been sold by its owner, MCI International. It is scheduled to stop broadcasting from the Point Reyes National Seashore next week.

The headquarters of station KPH sits on Point Reyes near Abbotts Lagoon, screened from the road by a colonnade of cypress trees. From adjacent antenna fields, radio operators inside receive messages from ships throughout the world and broadcast by remote from transmitters in Bolinas and the town of Chatham on Cape Cod, Massachusetts.

The only messages KPH handles are by Morse code and automated teletype machines, which transmit in Morse but print the words. In past decades, these high-frequency radio transmissions have become all but obsolete because of satellite technology, said Ray Smith, a KPH radio operator for 38 years.

Station Manager Jack Martini, who has worked at the site for 36 years and like Smith lives in Petaluma, said radio teletype has been usurped by the International Maritime Satellite System, a computerized network that allows agents to communicate directly with their ships at sea.

Some vessels no longer set out with a radio operator, he said, and with MCI's sale of KPH and its sister station, WCC in Cape Cod, only six marine radio stations remain.

There was a time, however, when every message destined to cross the Pacific was sent by high-frequency radio, and KPH was the flagship station of the Radio Corporation of America. "This facility was designed to be RCA's premier point-to-point radio station," Martini said.

The history of station KPH goes back to 1904, when it started broadcasting in San Francisco from the Palace Hotel, from which the station derived its acronymic name. After joining the Marconi Company in 1912, the pioneer station relocated to the east shore of Tomales Bay and built a transmitter in Bolinas.

It was Guglielmo Marconi, the father of wireless radio himself, who selected West Marin for the site of his Pacific operations. His decision was based on one factor alone: the place was virtually free from radio interference caused by electrical fields, thunder storms, and sun spots.

Marconi's radio network eventually proved so effective and vital to victory in World War I that it was deemed too important to be controlled by a foreigner. Westinghouse, AT&T, and General Electric joined forces in 1920 to take over Marconi's operations in the United States, forming the Radio Corporation of America.

RCA moved to G Ranch just before the Great Depression, paying the McClure family for over 2,000 acres in a condemnation hearing. Within three years they started operating from the concrete, two-story building that stands there today.

Throughout the years, KPH has continued broadcasting 24 hours a day. Smith said the station's peak operation was at the height of the Vietnam War, just before a cable was laid from Midway Island to Saigon. KPH radio operators were in contact back then with around 600 ships a day, most of them commissioned to supply American troops in Southeast Asia, he said.

Since then, it has been a long, slow decline for KPH, which like the rest of RCA, was acquired in 1986 by General Electric, which two years letter spun off the station to MCI.

All but about 25 acres of the property has become part of the National Seashore or the Coast Guard's Pacific communication station, which opened next door in 1973. AT&T operates a neighboring site to the west by remote. The AT&T site also handles ship to shore communications, but telephone calls only.

Station KPH attempted to operate its own satellite system in the 1970s, Martini said. Dish antennas were installed outside, and the entire upstairs was transformed into a control room. All that remains today from that experiment are a pair of back-up generators and two barn owls that nest in the gutted ceiling of the second floor.

Downstairs, the radio operators have time to read the newspaper and talk among themselves. A battery of teletype machines fills one room and runs nearly automatically. A cabinet full of receivers sends radio signals from planes throughout the Pacific to a company in the East Bay. The operators scan the airwaves. Messages wait for only 11 ships.

Philip Diehl monitors the teletype room. In his 31 years as a KPH radio operator, Diehl has handled distress signals, medical emergencies, and countless routine business messages.

"Twenty-five to 30 years ago, it was a lot of fun," he said, picking up ticker tape from the floor. "Now it's just sitting around, waiting for calls."