Comtech EF Data CDM-750, Installation And Operation Manual

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CDM-750 Advanced High-Speed Trunking Modem Revision 2
Introduction MN-CDM750
1–15
1.4.8 DoubleTalk
TM
Carrier-in-Carrier
®
(CnC)
Operating Mode Requires the two carriers in a duplex circuit to share a common frequency. Different symbol rates are
allowed.
CnC Ratio Ratio of Interferer Carrier Power to Desired Carrier Power (in dB). Positive values represent a stronger
Interferer Carrier, and negative values represent a stronger Desired Carrier. Range is +7 dB to -7 dB.
Symbol Rate Ratio 3:1 Tx/Rx or Rx/Tx
Inbound/Outbound frequency
uncertainty
±100kHz
Delay range 0 - 400 ms (230 - 290 ms factory default)
Es/No Degradation (dB)
measured at 0.0 dB CnC
Ratio QPSK, 0.3 dB
8-PSK, 0.3 dB
16-APSK, 0.6 dB
32-APSK, 1.0 dB
Monitor Functions •
Delay, in milliseconds
•
Frequency offset (between outbound interferer and desired inbound): 100 Hz resolution
•
CnC ratio, in dB (ratio of absolute power, outbound interferer to desired inbound)
CnC Monitor Accuracy ± 1.0 dB for symmetric symbol rate
1.4.9 Regulatory Compliance
“CE” as follows: EN 55022 Class A (Emissions)
EN 50082-1 (Immunity)
EN 60950 (Safety) EN 61000-3-2
EN 61000-3-3
EN 61000-4-2
EN 61000-4-4
EN 61000-4-5 EN 61000-4-6
EN 61000-4-8
EN 61000-4-9
EN 61000-4-11
EN 61000-4-13
FCC FCC Part 15 Subpart B
RoHS Compliance Yes
1.4.10 Standard Assemblies
Assembly Description Where Installed
PL-0000571 Modem Card
In chassis (top cover access)
PL-0000612 Main Card (includes Ethernet Interfaces)
PL-0000626 PIIC Motherboard Assembly
KT-0000150 AC Power Supply for modem (not BUC)