Comtech EF Data CDM-760 - Manual (Page 37)

Introduction Revision 2
CDM-760 Advanced High-Speed Trunking Modem MN-CDM760
1–11
1.3.3 Base Unit Connectors
Alarm Connector DB-15 male: Form C; Tx, Rx and unit faults; External Tx Carrier Off; IQ test point
Unit Management
DB-9 male with EIA-232 and RS 485 2W/4W
RJ-45 Ethernet (Maximum Ethernet packet size 10,240 bytes including Ethernet header & CRC)
Tx & Rx IF Connectors
70/140 MHz: BNC
L-Band: Type ‘N’ female
L-Band Monitor Type ‘SMA female
Traffic Data Interface
2X RJ45 10/100/1000 BaseT Ethernet
1X Optical Gigabit Ethernet (optional)
Note: All Data GigE interfaces have a maximum Ethernet packet size of 1632 bytes including
Ethernet header & CRC
1.3.4 Test Functions
Data Test Pattern 2^10-1, 2^15-1 and 2^23-1 compatible with BERT on applicable interfaces
CW Modulation disabled and CW signal is transmitted
SSB Carrier Provides suppressed carrier and suppressed sideband
Loopback Full Duplex only
1.3.5 Modulator (Dual IF)
70 / 140 MHz
Impedance / Connector
Output Power
Power Accuracy
50 to 180 MHz in 100 Hz steps, maximum symbol rate is within IF limits
75 Ω / BNC Female. Return Loss ≥ 18 dB
0 to -25 dBm, 0.1 dB steps (70/140 MHz)
±0.5 dB of nominal at 25°C. Within ±0.5 dB from 25°C value at same frequency
L-Band
Impedance / Connector
Output Power
Power Accuracy
950-2150 MHz in 100 Hz steps, modulator maximum symbol rate is within IF limits
50Ω, Type N Female. Return Loss ≥ 15 dB
-0 to -40 dBm, 0.1 dB steps
±0.5 dB of nominal at 25°C, ±0.5 dB from 25°C value at same frequency
L-Band Monitor
Port Impedance
Port Connector
Port Level
Port Isolation
Monitor Frequency
50 Ω (available in modulator only or modem configuration)
SMA Female
-27 dBm ± 3dBm
20 dB min
70/140 MHz: 900+70/140 MHz, L-Band: same.
Harmonics and Spurs < 60 dBc/4kHz, modulated carrier. Excludes spectral mask area.
External Tx Carrier Off TTL Low signal
Quadrature Phase Error and
Amplitude Imbalance
Sideband 35 dB below unmodulated carrier
Spectral Inversion Normal or Inverted
Carrier Phase Noise
Frequency Offset dBc/Hz Frequency Offset dBc/Hz
10 Hz -36 10 kHz -86
100 Hz -66 100 kHz -96
1 kHz -76 1 MHz -96
BUC 10 MHz Reference
Frequency Offset dBc/Hz Frequency Offset dBc/Hz
10 Hz -105 10 kHz -148
100 Hz -125 100 kHz -150
1 kHz -138