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CDM-Qx Satellite Modem Revision 5
Summary of Specifications MN/CDMQx.IOM
A–2
Output Connector
Type BNC Female (70/140MHz IF)
Type N Female (L-Band)
Output Return Loss
≥ 19 dB (70/140MHz IF)
≥ 10 dB (L-Band)
Clocking Options
Internal, ±1ppm or 0.1 ppm (SCT)
External, locking over a ±100 ppm range (TT)
Loop timing (Rx satellite clock) - supports asymmetric operation - Rx and Tx data rates do not
need to be identical
External Clock at transmit data rate.
External TX
Carrier Off
By TTL 'low' signal or external contact closure - hardware function automatically over-rides
processor
Figure A-1. Power Spectral Density Chart
-55
-50
-45
-40
-35
-30
-25
-20
-15
-10
-5
0
0.00
0.10
0.20
0.30
0.40
0.50 0.60 0.70 0.80 0.90 1.00 1.10 1.20
1.30
1.40 1.50
CDM-Qx Modulator
typically < -50 dB, and
guaranteed to be
< -45 dB at offsets
> 0.75 Rs
Comtech EF Data
CDM-Qx Transmit
Power Spectral Density,
referred to symbol rate
Symbol Rate, R
s
Spectral
density,
dB
Intelsat
IESS 308/309
Limit
Intelsat
IESS 308/309
Limit