Hill 640 Military Reservation


Historic California Posts, Camps, Stations and Airfields
Hill 640 Military Reservation
(Stinson Beach Fire Control Station, SCR-296 Radar Set No. 3)

Undated US Army Corps of Engineers History

Location: The entrance to the site is located approximately 1.25 miles east of the intersection of Panoramic Highway and State Highway 1 in Stinson Beach, Marin County, California

Site History: Hill 640 Military Reservation was acquired fee title to 0.954 of an acre and an easement of 1.610 acres, for a total of 2.564 acres of land from persons unknown on February 16, 1940 for use as a fire control station. In 1942, the Army acquired fee title to 3.620 acres, for a total acquisition of 6.184 acres of land. On October 31, 1951, the 6.184 acres for Hill 640 Military Reservation were transferred to the Navy. However, the acreage was deleted from transfer to the Navy by a letter from the Secretary of the Army on November 28, 1952. On May 22, 1959, 6.18 acres of the 6.184 acres were reported excess to the GSA. The 6.18 acres were then quitclaimed to a private party on July 11, 1960.

Source: US Army Corps of Engineers Public FUDS GIS Site

Additional Information: The Site was defended by two .50 Caliber Machine Gun adjacent to SCR-296 Radar Set No. 3, see map below.


SCR-296 Radar Set No. 3 Supporting Battery Smith, Fort Barry


Typical installation of an SCR-296 radar set.

Description: Fixed Coast Artillery gun-laying medium wave radar, assigned to modern 6 inch or larger batteries.

Uses: Set is designed to track a surface target in range and azimuth. Data are sent to the plotting room and used in firing. An SCR-296-A normally is assigned to one battery, but may furnish data to more. Works with IFF RC-136-A.

Performance & Sitting: Range is shown on "A" scope. The target is tracked in azimuth with a pip matching oscilloscope or a zero-center meter. Range accuracy is about ± 30 yards while azimuth accuracy is about ± 0.20 degree under the best conditions. The set has a dependable range of 20,000 yards on a destroyer size target when employed at a height of 145 feet. Site should be not less than 100 feet above sea level; 150 to 500 feet is recommended.

Mobility: Shipment includes areas and separate generator. When crated the total weight is 91,763 lbs. Largest unit is 5,270 lbs.

Installation: SCR-296-A includes a tower, an operating building, and two power plant buildings. The tower is obtainable in heights of 25, 50, 75, and 100 feet. Concrete floors must be put in locally.

Personnel: Operating crew consists of 5 men in addition to a power plant operator and maintenance man who should be available at all times.

Power: Primary power of 2.3 KW is supplied by PE-84C -- commercial or auxiliary 110 V, AC single phase. Generator needs high octane gasoline.

Information from Naval History Library Online.






Site Maps






Additional Online Histories:







Search our Site!
Search the Web Search California Military History Online

Questions and comments concerning this site should be directed to the Webmaster


Updated 8 February 2016

Description:	Fixed Coast Artillery gun-laying medium wave radar, assigned to modern 6 inch or larger batteries.
Uses:	Set is designed to track a surface target in range and azimuth. Data are sent to the plotting room and used in firing. An SCR-296-A normally is assigned to one battery, but may furnish data to more. Works with IFF RC-136-A.
Performance & Sitting:	Range is shown on "A" scope. The target is tracked in azimuth with a pip matching oscilloscope or a zero-center meter. Range accuracy is about ± 30 yards while azimuth accuracy is about ± 0.20 degree under the best conditions. The set has a dependable range of 20,000 yards on a destroyer size target when employed at a height of 145 feet. Site should be not less than 100 feet above sea level; 150 to 500 feet is recommended.
Mobility:	Shipment includes areas and separate generator. When crated the total weight is 91,763 lbs. Largest unit is 5,270 lbs.
Installation:	SCR-296-A includes a tower, an operating building, and two power plant buildings. The tower is obtainable in heights of 25, 50, 75, and 100 feet. Concrete floors must be put in locally.
Personnel:	Operating crew consists of 5 men in addition to a power plant operator and maintenance man who should be available at all times.
Power:	Primary power of 2.3 KW is supplied by PE-84C -- commercial or auxiliary 110 V, AC single phase. Generator needs high octane gasoline.
	Information from Naval History Library Online.