Ericsson MX8400, Справочное руководство

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Technical Specification
B.4 Reference Signals
B.4.1 Internal Reference
Internal reference signals are generated to provide locking and synchronization
sources.
Table B.9 Internal Reference Specification
Item Specification
Accuracy ± 0.2 ppm or better
Aging ± 0.1 ppm per year
Locking (power-on
configuration cycle
or a reconfiguration
cycle) Internal Reference should be valid for normal operation within
1 second of the completed clock configuration cycle.
If configured to lock to HSYNC input, the internal frequency
reference may not be in a locked state within the 1second period.
Drift
From a locked state the Internal frequency should not drift more
than 0.2 ppm within a 24-hour period when in holdover operation.
B.4.2 H SYNC IN
External studio clock reference is configurable to accept 625 or 525 line video
standards.
Table B.10 HSYNC IN Specification
Item Specification
Safety status SELV
Connector
designation HSYNC IN 1
HSYNC IN 2
Connector type
75
Ω
BNC female socket
Input standard 625 line PAL, 525 line PAL-M or 525 line NTSC, chrominance not
required.
Input level
1 V pk-pk nominal
±
5%
Cable length 250 m, maximum
Return loss Better than 30 dB up to 6 MHz
Input impedance Selectable between 75 Ω and high impedance.
When powered off, the HSYNC input is high impedance.
Loss of HSYNC IN The Multiplexer maintains normal operation in the event of input
HSYNC reference loss. In the event of a loss of input HYSNC signal
the multiplexer holds over the last known good HSYNC input
frequency until the HSYNC input becomes valid.
2/1553-FGC 101 1014 Uen B B-9