Symmetricom ET6000, Руководство пользователя

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OPERATION
In this mode, after an initial warm-up delay, and an oscillator stability check/delay, the
unit will be in the Dynamic mode and will begin doing position averaging. The position
average is actually a running average of each subsequent position value. The number of
averages is user selectable but the default number is 200. A position fix takes
approximately three seconds, so the position averaging itself could take about ten
minutes.
Once the unit has completed its position averaging, it will switch to the Unit Stabilizing
mode. At this time, the 1pps will be coherent with the internal disciplined 10MHz
oscillator, and the oscillator discipline process begins. At the end of Unit Stabilizing, the
front panel LOCKED LED will illuminate.
For additional information on the “AUTO” mode, see Chapter Five.
Choice “1>STATIONARY” (Timing Mode)
Depressing the “1” keyboard switch selects the “STATIONARY” Mode. Pressing the
MENU keyboard switch returns the display to the SET-UP MENU SCREEN.
The “
STATIONARY ” (Timing) mode is the most frequently used mode of operation for
timing applications. This mode of operation assumes that the current position (longitude,
latitude, and altitude) is accurate. It uses an averaged solution of the time information
from as many satellites as the receiver is tracking, up to eight.
For additional information on the “
STATIONARY ” mode, Chapter Five.
Choice “4>DYNAMIC” (Survey Mode)
Depressing the “4” keyboard switch selects the “ DYNAMIC ” mode and the “Operating
Mode” changes to “ Survey Mode ” Pressing the MENU keyboard switch returns the
display to the SET-UP MENU SCREEN.
This choice forces the GPS Receiver to remain in the position survey mode at all times.
When three satellites are in view, the unit will perform two-dimensional “position fixes”
(latitude, and longitude). When four satellites are in view, the unit will perform three-
dimensional “position fixes” (latitude, longitude, and altitude).
For additional information on the “
DYNAMIC ” mode, see Chapter Five.
Choice “5>FW” (Flywheel Mode)
Depressing the “5” keyboard switch selects the “FLYWHEEL” mode and the “Operating
Mode” changes to “FLYWHEEL.” Pressing the MENU keyboard switch returns the
display to the SET-UP MENU SCREEN.
Symmetricom Inc ET6xxx ExacTime GPS TC & FG (Rev C) 3-11