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CXR Larus 80-100-400 Issue 2 July 2006 page
3-33
Front Panel Label
LED Color
Indication
FAIL Red
Card
fail
INPUT A
Green
Input A select, tracking
INPUT B
Green
Input B select, tracking
HOLD
Yellow
Hold, not tracking
ACQUIRE
Green
Acquiring reference signal
LOCKED Green
Locked
(normal)
FREERUN
Yellow
Free run, not tracking
ACTIVE
Green
Driving output cards
GPS
Green
Global Positioning System, tracking GPS signal
DEGRADED
Yellow
Degraded, tracking in Stratum 1/PRC degraded
region
3.3631 Controls and Monitoring:
a. Test pushbutton (press for up to 6 seconds). In the DS1/E1 tracking state
only, momentary hold test; display shows 'H' if successful. (There is no
response in the GPS mode.) Does not disrupt tracking. In invalid output
state, resets tracking algorithm to FREERUN state; display shows 'r'. (An
internal TEST/RUN toggle, S2, is set in RUN mode for normal operation.)
b. Monitor jack (-20 dB), framed all ones at clock output frequency.
c. Software control for setting SF/ESF or CCS/CAS framing on both input
channels.
d. EEPROM for storing last best guess for DDFS.
e. Flash EPROM for software updates.
f. Temperature sensor for future software algorithms for temperature
compensated holdover.
g. Predictive holdover feature that remembers the average correction it has
been making and continues the average correction while in holdover to
cancel aging.
3.3632 Seven Segment Status Display:
a. Status conditions while in tracking or acquisition state (display blinks every
1 to 2 seconds):
.
ACQUIRE 1 state (single dot).
o
At top of display: Normal tracking, no phase error.
Alternates with display of input reference.*
o
At bottom of display: Correction in progress due to more than 1/4
bit phase change.*
P
Displayed momentarily immediately after power-up if input card is
