Comtech EF Data CDM-760 Installation And Operation Manual page 126

Front Panel Operation
CDM-760 Advanced High-Speed Trunking Modem
(CONFIG: INTF) (PIICX=OC3/STM1)  ClkSource  RXClock
Set the clock source by which Rx data is clocked out of the OC3/STM1 interface to the
external baseband equipment. Use the  arrow keys to select RX SAT or TX CLK.
Press ENTER.
(CONFIG: INTF) (PIICX=OC3/STM1)  Mask
Mask: TxPll:Fault
InpSigLoss:Alarm
Mask: RxPLL:Fault
These menus set how the modem reports interface alarm or fault states. Use the   arrow
keys to select TxPll or InpSigLoss or more... to go to the next screen. There, use the   arrow
keys to select RxPll, RxOF, or RxUF. Press ENTER.
Note the following:
Selection (Alarm)
TxPLL
InpSigLoss
RxPLL
RxOF
RxUF
Use the  arrow keys to set the report state for each selection as Alarm, Fault, Mask, or
Fault-Tx On. (The RxPll, RxOF, and RxUF selections provide only Alarm, Fault, and Mask.) Press
ENTER. Note the following:
Mask Type
Alarm
Comtech EF Data strongly suggests that you select TX CLK, unless a high-
stability EXT CLK is present and timing of the network requires all devices to
be locked to the EXT CLK.
Comtech EF Data strongly suggests that you select RX SAT, unless a high-
stability EXT CLK is present and timing of the network requires all devices to
be locked to the EXT CLK.
RxUF:Alarm
Description
The Tx Clock PLL is railed high or low, meaning that the Tx Clock Source is significantly
different than the rate of the transmitted data.
Input Signal Loss means that the PIIC OC3/STM1 module TX-IN connector finds no traffic.
The Rx Clock PLL is railed high or low, meaning that the Rx Clock Source is significantly
different than the rate of incoming data.
Rx Overflow means that the demodulator traffic is too fast for the RxClock clock setting. This
causes the buffer to overflow and to re-center, losing data in the process.
Rx Underflow means that the demodulator traffic is too slow for the clock RxClock setting.
This causes the buffer to underflow and to re-center, losing data in the process.
Unit Status
Fault State
LED Color
Amber None
more.... ()
RxOF:Fault
Causes
Mutes
Redundancy
Tx Carrier
Switch
No No
6–37
Revision 4
MN-CDM760
()
Visible Location
Monitor: Live Alarms menu