Comtech EF Data CDM-625A, Installation And Operation Manual

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CDM-625A Advanced Satellite Modem MN-CDM625A
Front Panel Operation Revision 4
6–34
6.2.1.5.4 CONFIG: Clocks

Freq-Ref
Frequency Reference: Internal
(Internal(with O/P),1,2,5,10MHz) (

)
Use the
▲▼
arrow keys to select one of the two internal reference modes – Internal and
Internal (with Output) – and then press ENTER .
Internal (with Output)
mode uses the internal reference as an output on the rear panel
Ext Ref
In/Out BNC connector. This mode is useful if a user wishes to use a single frequency reference
for both the modem and another piece of equipment in the system. When you select this mode,
an amber LED adjacent to the connector illuminates to alert you that the connector, normally
used as input, now has an output signal present.
6.2.1.5.5 CONFIG: Clocks

Int-Ref-Adjust
Internal Hi-Stability 10MHz Reference
Fine Adjust: +048 (+/-999) (

)
Use this menu for very fine adjustment of the Internal 10MHz Reference. When you select the
Internal 10 MHz Reference, the adjustment value is retained in EEPROM memory, and is
therefore not lost when the NVRAM memory 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 adjust value occur immediately upon entry, not after Press ing
the ENTER key.