Master Control Station

• History of GPS Operations at SLAC
• Regional Network Analysis
• Data Flow
• Time Series
• Official Coordinates for SLAC M40
• Download RINEX observation files

SLAC’s GPS master control station SLAC M40 is located next to the Sector 30 gate at the end of the linac. The actual control point is located on top of a 60 cm diameter concrete pillar with the top about 3 m off the ground. A wooden deck surrounding the concrete cylinder provides access. The actual receiver is a Leica System RS 500 Receiver that is housed in a weatherproof box attached to the deck. The AT-504 choke ring antenna is attached to the top of the pillar using a Kern forced centering mount. To protect the instruments from lightening, a lightening arrester is installed at M40.

This control monument was chosen for several reasons:

• Central SLAC location
• Monument within controlled area of SLAC
• Amount of visible sky is large enabling better GPS geometry
• RTK radio-modem coverage of SLAC nearly perfect
• Permanent power access and potential network connectivity
• Easy access for monitoring the equipment
• Pillar and deck are in good condition