Comtech EF Data CDM-425, Installation And Operation Manual

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CDM-425 Advanced Satellite Modem
Revision 0
Front Panel Operation 6–23 MN-CDM-425
6.2.1.4 CONFIG: Rx
RxIF Freq FEC Demod Data Descram EbNo
(Data 02048.000kbps,02184.533ksps) (

)
On the top line – Use the
◄ ►
arrow keys to select a parameter. Press ENTER.
On the bottom line – Read-only Data/Symbol rate information is provided.
1. When CONFIG: Mode = IP-ACM or V2-ACM, EbNo on the top line of this
display is replaced by SNR.
2. When Sub-Mux is ON, the Data Rate information on the bottom line of this
display is replaced by Composite Rate information.
6.2.1.4.1 CONFIG: Rx

Rx-IF
Rx: Acquisition Sweep Range = +/- 032 kHz
SpectrumInvert=Off Rx
α=.35(.35,.12)(

)
Use the
◄ ►
arrow keys to select a parameter. Press ENTER .
Acquisition Sweep Range – The Acquisition Sweep Range value determines the amount of
frequency uncertainty the demodulator will sweep over in order to find and lock to an incoming
carrier. When operating at low bit rates, large values of sweep range (compared to the data rate)
cause excessively long acquisition times.
The Rx symbol rate determines the Sweep Range limits:
Rx Symbol Rate Sweep Range Limit
±1 to symbol rate / 2 (ksps) 18-64 kbps
±1 to 32 kHz 64-389 ksps
±1 to (10% of symbol rate) 389-3000 ksps
±1 to 300 kHz >3000 ksps