Part of the On the Land series at Commonweal New School
Co-presented with the Maritime Radio Historical Society
In February 1914 the American Marconi Telegraph Company began operating a powerful transmitting station on the Bolinas mesa, where Commonweal would be decades later. This station, along with its companion receiving station in Marshall, with its enormous spark transmitter of 230 kilowatts, reached across the Pacific to Hawaii and, later, to Asia. Telegrams were sent and received along this route in competition with the undersea cables which, until then, held a monopoly on intercontinental communications. In 1920 the Radio Corporation of America (RCA) absorbed the Marconi company and replaced the spark transmitter with two even more powerful machines known as Alexanderson alternators. In that same year RCA added Morse code ship to shore service at the site using the famous call letters KPH.
Today these transmitters, some more than 80 years old, can be seen in full-throated action, communicating with ships at sea as KPH has always done. The Bolinas site is the only place remaining in the world where a fully operational Morse code coast station from the golden age of radio may still be seen in action.
As part of Commonweal’s 50th anniversary year celebrations, please join the Maritime Radio Historical Society’s Richard Dillman (call name W6AWO), for this tour of the radio facilities in the “back half” of the Commonweal main building.
Image: The Marconi transmitting station (which would become Commonweal) being constructed in 1912. Courtesy: Maritime Historical Radio Society.