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LCS-4 L-Band Combiner Switch
Front Panel Control
7.3.3 LNB V
OLTAGE
Contact Comtech EF Data Customer Support for a procedure for setting the CAL current for the
LNB in the event it uses an internal ovenized oscillator. These units draw a higher current at turn
ON of the LNB voltage in order to heat up the crystal. After warm-up, the current drops back to
the normal steady-state value.
7.3.4 ODU/BUC
Note: User shall use ODU/BUC or LNB Switch with indicator contacts.
The RED condition indicates the ODU Switch has failed. The switch has a set of indicator
contacts that are read by the unit controller to determine the position of the switch. When the A/B
indicator does not agree with the programmed position:
•
•
7.4 F
D
AULT
EFINITIONS FOR
TX Faults
RX Faults
Common Faults
Switchover Time
Automatic Switchover
Manual Switchover
Modulator TX Carrier ON/OFF
/C
T
URRENT
URN
LNB O
OR
NLINE
Contact Comtech EF Data for a procedure to correct the problem.
A RED failure is activated if it is not possible to correct position of the switch.
Table 7-1. Fault Definitions for Switchover for LNB or ODU/BUC
ON
S
WITCH
S
WITCHOVER FOR
Characteristics
BUC Power Supply HI or Low Voltage Alarm
BUC Current HI or Low Current Alarm
LNB Power Supply HI or Low Voltage Alarm
LNB Current HI or Low Current Alarm
10 MHz failure – reference to the BUC or LNB is compromised.
Shut off the 10 MHz to the BUC and LNB
Less than 1.5 second following fault detection.
The starting point assumes both units are good. When a fault
occurs in the ONLINE unit, it is replaced only with a functional
standby unit. No switching occurs if both units have failed.
From front panel or remote port.
Unit senses modulator faults and applies control (bypasses UP)
to turn TX carrier Off at modulator for up to four modulators.
7–7
MN/LCS4.IOM
LNB
ODU/BUC
OR
Revision 1
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