Config) Rx: Esno; Config: Clocks; Config) Clocking: Freq-Ref; Config) Clocking: Int-Ref-Adjust - Comtech EF Data CDM-750 Installation And Operation Manual

CDM-750 Advanced High-Speed Trunking Modem
Front Panel Operation

5.2.2.1.3.7 (CONFIG) Rx: EsNo

To edit the EsNo Alarm Point: First, use the
the arrows keys to edit the value of that digit. Note the following:
▲ ▼
•
The permitted range is from 00.1 to 16.0 dB.
•
If the Rx Es/No falls below this value and the fault is NOT masked, a receive traffic fault
will be generated.
Press ENTER when done.
5.2.2.1.4

CONFIG: Clocks

Clocking:
◄ ►
Use the arrow keys to select Freq-Ref or Int-Ref-Adjust, and then press ENTER.

5.2.2.1.4.1 (CONFIG) Clocking: Freq-Ref

Frequency Reference: Internal
(Internal(with O/P),1,2,5,10MHz)
Use the arrow keys to select Internal, Internal+O/P, Ext 1MHz, Ext 2MHz, Ext 5MHz,
▲ ▼
or Ext 10MHz, and then press ENTER. Note the following:
•
Selection of Internal mode frequency-locks the modem to the high stability ±0.06 ppm
10 MHz internal oscillator.
•
In the Internal+O/P (Internal with Output) mode, the 10 MHz internal reference is used
as an output on the rear panel J8 | Ext Ref BNC connector. This mode is useful when the
user wishes to use a single frequency reference for both the modem and another piece of
equipment in the system. When this mode is selected, a green LED adjacent to the
connector illuminates to alert the user that the connector, normally used as input, now has
an output signal present.
•
Selection of the Ext 1 MHz, Ext 2 MHz, Ext 5 MHz, or Ext 10 MHz modes will
frequency lock the modem to an injected external reference on the rear panel J8 | Ext Ref
BNC connector.

5.2.2.1.4.2 (CONFIG) Clocking: Int-Ref-Adjust

Internal Hi-Stability 10MHz Reference
Receive EsNo Alarm Point = 02.0 dB
Freq-Ref
Fine Adjust: +048 (+/-999)
◄ ► arrow keys to select a digit to edit, and then use
Int-Ref-Adjust
5–19
Revision 1
MN-CDM750
v)
(
( )
(v)
(34v)