Comtech EF Data CDM-760, Инструкция по установке и эксплуатации

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Front Panel Operation Revision 4
CDM-760 Advanced High-Speed Trunking Modem MN-CDM760
6–50
Mask Type Unit Status LED Color Fault State Visible Location
Mask None None
None: A masked event is not
logged and is not seen in
any menu.
Fault-Tx On Red J1 Alarm Connector Monitor: Stored-Events log
6.2.2.12 (CONFIG:) Ref
Modem Reference: Internal
Internal Ref Fine Adjust:-001 (  )
Use the
 
arrows keys to select Modem Reference or Internal Ref Fine Adjust. Press ENTER .
6.2.2.12.1 (CONFIG: Ref) Modem Reference
Use the

arrow keys to select a parameter. Press ENTER .
Note the following:
• Select Internal mode to frequency-lock the modem to the high stability ±0.06 ppm 10 MHz
internal oscillator.
•
Select
IO/P
(Internal with Output) mode to use the 10 MHz internal reference an
output on the rear panel J8 | EXT REF BNC connector. This mode is useful when you desire
to use a single frequency reference for both the modem and another piece of equipment in
the system. When selecting this mode, a green LED adjacent to the connector illuminates to
alert you that the connector, normally used as input, now has an output signal present.
•
Select the Ext 1 MHz , Ext 2 MHz , Ext 5 MHz , or Ext 10 MHz mode to frequency-lock the
modem to an injected external reference on the rear panel J8 | EXT REF BNC connector.
6.2.2.12.2 (CONFIG: Ref) Internal Ref Fine Adjust
With the Internal 10 MHz Reference selected, very fine adjustment of the Internal 10 MHz
Reference is possible. The adjustment value is retained in EEPROM memory, and is therefore
not lost when the NVRAM is cleared.
Use the
 
arrow keys to select a digit, and then use the

arrow keys to change that digit.
Press ENTER .
Changes made to the adjustment value take effect immediately, not after the
ENTER key is pressed.