EndRun Tempus LX GPS, User Manual

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T e m p u s L X G P S U s e r M a n u a l 36
C H A P T E R F I V E
37 T e m p u s L X G P S U s e r M a n u a l
F R O N T - P A N E L K E Y P A D A N D D I S P L A Y
than 55,000 will set the DAC fault flag that will appear in the fault status display. The Time/Status
display will also indicate a fault condition.
The oscillator type indicates the oscillator that is installed. Possible oscillator types are:
Temperature-compensated crystal oscillator (TCXO)
Medium-stability oven oscillator (MS-OCXO)
High-stability oven oscillator (HS-OCXO)
Rubidium oscillator (Rb)
Antenna Fault Mask
This setting allows you to prevent the antenna fault from creating an alarm conditon. Some instal-
lations may need to mask this fault due to special antenna situations like splitters or DC blocks that
confuse the antenna detection circuit.
Signal Loss Fault Mask
This setting allows you to prevent a signal loss fault from creating an alarm condition. Some installa-
tions may need to mask this fault when operating the NTP server as a Stratum 2 server.
Clock Menu
The Clock Menu provides access to the parameters related to timekeeping. These are Time Mode,
Local Offset, Hours Format, and Daylight Savings Time. These displays are all described below.
Time Mode
Time mode defines the time format used for the front-panel time display and, if installed, the optional
time code or Serial Time output. The time mode does not affect the NTP output, which is always
UTC. Possible values for the time mode are GPS, UTC, and local time. GPS time is derived from
the GPS satellite system. UTC is GPS time minus the current leap second correction. Local time is
UTC plus local offset and Daylight Savings Time. The local offset and daylight savings time displays
are described below.
Local Offset
Local offset is used in calculating the current local time when the time mode is set to local (see time
mode above). Press the EDIT key to change the value. Enter a negative offset for time zones west of
the Greenwich meridian, and a positive offset for time zones to the east. If enabled, DST will add an
additional hour.
Hours Display
The hours-display format affects the front-panel time display and is active only when the time mode
is set to local time. Hours-display selections are either 12-hour format (1-12 hours with AM/PM
indicator) or 24-hour format (0-23 hours).
Daylight Savings Time
Daylight Savings Time (DST) is used in calculating the current local time when the time mode is set
to local. When the time mode is local this display will allow the user to enable or disable DST by
pressing EDIT. If DST is disabled then any previously set start and stop times will be ignored. If
DST is enabled then the start and stop times can be set by pressing the arrow keys to scroll and then
ENTER. DST is active within the start-stop interval and adds one hour to the local time. If DST is
active the display will show an active indicator.