INTRODUCTION. Masterclock GPSPCI

INTRODUCTION

The GPSPCI is a PCI card that provides very stable accurate time and date information for a

Windows PC. The card receives reference time information from Atomic Clocks in the GPS

(Global Positioning System) satellites.

GPS SATELLITES

The GPS satellites are operated and maintained by the US Department of Defense and allow for the precise determination of local time and location at any point on (or above) the Earth. This is accomplished via the transmission of very accurate timing information from a series of satellites that provide coverage of the entire planet.

The GPSPCI extracts timing reference from these signals and generates time information to the

PC that is synchronized to within less than 10 microseconds of UTC (Universal Coordinated or

Greenwich Mean Time).

UTC/GREENWICH MEAN TIME

UTC is the local time at the prime reference meridian at Greenwich, England. At a given location on the planet, local time can be displaced (referenced to UTC) by -11 to +12 hours.

North and South America are from -3 to -11 hours delayed; most of Europe and Africa and all of

Asia and Australia are advanced by +1 to +12 hours.

TIME ZONES & DAYLIGHT SAVING TIME

The GPSPCI provides UTC to the PC’s operating system. Time zone offsets and daylight savings time are handled as a standard feature of the operating system.

INITIAL OPERATION

Each GPSPC is thoroughly tested with its external antenna prior to shipment. Physical installation is simply a matter of installing the card into a PCI or ISA bus slot and connecting the antenna.

OPERATING THE GPSPCI FOR THE FIRST TIME

When the GPSPCI is initially powered up, after having been shipped to a new location, the time to first fix (time the unit takes to acquire satellites and extract correct time) could be up to 25 minutes although it is typically 5 - 15 minutes. Factors such as atmospheric conditions, antenna type, antenna location, and antenna cable length will affect the time to first fix.

The GPSPCI will provide time from an internal on-board clock whenever GPS time is not available. The onboard clock runs from a backup battery in the absence of power from the PC.

GPSPCI 2/72008 Rev 1.2.1

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