Comtech EF Data CDM-760 - Page 126

Front Panel Operation Revision 4
CDM-760 Advanced High-Speed Trunking Modem MN-CDM760
6–37
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.
(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.
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.
(CONFIG: INTF) (PIICX=OC3/STM1)  Mask
Mask: TxPll:Fault
InpSigLoss:Alarm more…. ()
Mask: RxPLL:Fault RxOF:Fault
RxUF:Alarm ()
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)
Description
TxPLL
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.
InpSigLoss
Input Signal Loss means that the PIIC OC3/STM1 module TX-IN connector finds no traffic.
RxPLL
The Rx Clock PLL is railed high or low, meaning that the Rx Clock Source is significantly
different than the rate of incoming data.
RxOF
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.
RxUF
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.
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
Unit Status
LED Color
Fault State
Causes
Redundancy
Switch
Mutes
Tx Carrier
Visible Location
Alarm
Amber None No No Monitor: Live Alarms menu