Intercept and DF Stations in the Pacific
STATION ABLE
The first Navy shore-based intercept station was established in the American consulate in Shanghai in 1924, and was designated Station ABLE. The primary target of intercept was the diplomatic radio network serving the numerous Japanese consulates throughout China.
STATION CAST
In 1928, the Commander-in-Chief of the Asiatic Fleet, Admiral Frank B. Upham, was so impressed with the radio intelligence activities that he wanted to establish a radio intelligence center in his command. Specifically, he requested that an intercept unit complete with a decryption center be located in or near Manila Bay, with the mission of preventing surprise attack.
STATION S
The Research Desk at OP-20G first established Station S in 1932 at Fort Stevens, just outside of Astoria, Oregon. Chief Radioman Dorman Chauncey, one of the first five self-taught On-The-Roof Gang members known as Class #0, assessed the location wasn't optimal for intercept operations, but the site was vacant and ready for occupation. More valuable, the site would be co-located with a main U.S. Navy radio station, callsign "NUZ," which could procure radio equipment without drawing undue attention and would help keep maintenance costs for the intercept site down.
STATION BAKER
Located halfway between Hawaii and the Philippine Islands, the island of Guam was of great strategic interest to the U.S. Navy. Long before World War II, it was a communications relay post and coal depot for the Navy.
STATION HYPO
Station HYPO was first established in 1928 at Little Wailupe on the southeastern shore of Oahu. The intercept site was built into a small, cramped storeroom. Even though it was the farthest U.S. Navy intercept station from Japan, it enjoyed good intercept conditions for the Japanese Imperial Navy (IJN) during the nighttime hours.