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
6–42
•
Below 64 ksymbols/sec: ±1 to ±(Rs/2) kHz, where:
Rs=symbol rate in ksymbols/sec
•
Between 64 and 389 ksymbols/sec: ± 1 up to a maximum of ± 32kHz
•
Above 389 ksymbols/sec: ±1 to ± (0.1Rs) kHz, up to a maximum of ± 200 kHz
This range is pre-calculated and displayed in parentheses for reference.
6.2.1.8.3 CONFIG: CnC

Search-Delay
CnC Search Delay: (range 0-330ms)
Min: 010 ms Max: 290 ms (

)
You may apply restrictions to the range of delay used by the search. This will reduce the time it
takes for the CnC algorithm to converge
Edit the Min or Max delay by using the ◄ ► arrow keys to select a digit. Then, use the
▲▼
arrow keys to change that digit. Press ENTER .
During initial link testing, you should set Min delay to 240 ms and Max delay to 300 ms . Once
CnC finds the exact delay, you can further reduce the values, but you must take care to allow
sufficient range to accommodate changes in path delay due to Doppler.
When you are bench-testing CnC with two units in a back-to-back configuration, the
minimum delay should be set to 0 ms, and the maximum to 20 ms. This takes into
account the lack of satellite delay.