 Its identifier is "OSI" and publicly available FAA documents show the VOR signal is on 113.9 MHz.Many of the area's characteristic redwood-log homes were first built in the early 1930s by a developer who subdivided a few tracts and established a water supply and reservoirs dedicated to the new community.The redwood "logs" came from unused railroad-tie stock sawn by a mill located at the intersection until the Depression.