KFS WebSDR is co-located with the KFS Kiwi high-frequency radio receiver station near the mouth of Lobitos Creek, about 5.5 miles (9 km) south of Half Moon Bay and 0.8 miles (1.3 km) west of Lobitos, California. For many years this station provided continuous-wave radio communications for ships at sea. By 1995, the U.S. Coast Guard and military no longer used this technology; however, there were about 150,000 ships around the world that still used continuous-wave radio to transmit messages via Morse code. The expense of retrofitting these ships for satellite communications was prohibitive, so some of these critical shore stations were purchased and updated expressly for this market.
In July 1910, a transmitter designated “KFS ” was put into operation at Ocean Beach in San Francisco by the Poulsen Wireless Telephone and Telegraph Company. In 1932, a receiving facility was constructed on 200 acres (81 ha) near Lobitos on Half Moon Bay by the Mackay Radio and Telegraph Company. The International Telephone and Telegraph Company subsequently purchased these stations and operated them for many years under the name Globe Wireless. Eventually, in the early 1990s, the facility was sold to a group of local investors that modernized the network and continued using the Globe Wireless name.
By early 2000, the Half Moon Bay facility had become the central control, database server farm, and west coast receiving site for the Globe Wireless data and email network providing global email and data to 40,000 commercial shipping vessels from stations at 23 sites. In 2013, Globe Wireless was purchased by Inmarsat and the high-frequency radio portion of the operation was retained under the name Globe Wireless Radio Services. Currently, the Half Moon Bay KFS site is also in use by radio providers serving the aeronautical, cellphone, emergency response, internet data, and military communities. Today, there are four receive-only high-frequency antennas. Antenna and rack space facilities are provided as a public service by Globe Wireless Radio Services. Read more here and here. Explore more of the KFS HF Receiver Station and Half Moon Bay here: