Appendix A. Summary Of Specifications; Modulator; Figure A-1. Power Spectral Density Chart - Comtech EF Data CDM-Qx Installation And Operation Manual

CDM-Qx Satellite Modem
Summary of Specifications
Power accuracy
Output Connector
Output Return Loss
Clocking Options
External TX
Carrier Off
0.00 0.10
0
-5
Comtech EF Data
CDM-Qx Transmit
-10
Power Spectral Density,
referred to symbol rate
-15
-20
-25
-30
-35
-40
-45
-50
Spectral
density,
dB
-55
±1.0 dB over frequency, temperature, and number of modulators installed in the chassis
Type BNC Female (70/140MHz IF)
Type N Female (L-Band)
≥ 19 dB (70/140MHz IF)
≥ 10 dB (L-Band)
Internal, ±1ppm or 0.06 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.
By TTL 'low' signal or external contact closure - hardware function automatically over-rides
processor
0.20 0.30 0.40 0.50
Intelsat
IESS 308/309
Limit

Figure A-1. Power Spectral Density Chart

0.60 0.70 0.80 0.90
CDM-Qx Modulator
typically < -50 dB, and
guaranteed to be
< -45 dB at offsets
> 0.75 Rs
A–2
MN/CDMQx.IOM
1.00 1.10 1.20 1.30
Symbol Rate, R
Intelsat
IESS 308/309
Limit
Revision 6
1.40 1.50
s