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CXR Larus 80-100-400 Issue 2 July 2006 page
3-23
3.3526 Input
Sensitivity:
0.3 to 1.5 volts RMS
3.3527 Jitter
Tolerance:
Does not apply
3.3528 Input Signal Selection:
Track and Hold Card A lights the Input A LED when it is tracking Input A and the
Input B LED when it is tracking Input B. In the AA architecture, Track and Hold Card
B does the same. In the AB architecture, Track and Hold Card B lights the Input A
LED when it is tracking Input B and the Input B LED when it is tracking Input A.
Selection of the other input can be done by a track and hold card when it detects a
problem with the input or by command from the 54550 Information Management
Card.
3.3529 External
Reference/Input:
5 MHz or 10 MHz at 0.3 to 1.5 volt RMS into an impedance of 50 ohms
This feature is not available for reference replacement on the track and hold cards
but can be used as tertiary input (i.e., able to be tracked).
3.3530 Oscillator:
Minimum accuracy of <±1.6 x 10
-9
Rubidium oscillator standard; performance exceeds ANSI, Bellcore Stratum 2, and
ITU-T TNC specifications. The oscillator outputs a frequency of 50.255055 MHz;
therefore a divide by 5 circuit is added before the phase measurement circuit. A 10
MHz rubidium is also used.
3.3531 Long Term Drift (1 year):
1.544 MHz ±5 x 10
-10
(±7.72 x 10
-4
Hz)
3.3532 Pull-in
Range:
1.544 MHz ±1.6 x 10
-8
(±2.47 x 10
-2
Hz)
2.048 MHz ±2.6 x 10
-8
(±0.04 Hz)
Will not track any phase transient greater than 8 UI.
3.3533 Holdover Drift (after 1 month stabilization):
<7.5 x 10
-11
per day, over any ±10
°
C temperature range
<1 x 10
-10
after one month, over ±10
°
C change within 24 hours
3.3534 Traceability:
<1 x 10
-11
3.3535 Warmup
Time:
Approximately 10 minutes from cold start
