Comtech EF Data CDM-425, Installation And Operation Manual

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CDM-425 Advanced Satellite Modem
Revision 0
Introduction 1–16 MN-CDM-425
Output power 950-2250 MHz band: 0 to -40 dBm, 0.1 dB steps - manual mode. Also see AUPC section.
50-180 MHz band: 0 to -25 dBm, 0.1 dB steps - manual mode. Also see AUPC section.
Power accuracy 950-2250 MHz band:
±0.5 dB over frequency, data rate, modulation type and temperature range 15°to 35°C
±0.8 dB over frequency, data rate, modulation type and temperature range 0° to 50°C
50-180 MHz band:
±0.5 dB over frequency, data rate, modulation type and temperature range 15° to 35°C
±0.7 dB over frequency, data rate, modulation type and temperature range 0° to 50°C
Output impedance
950-1950 MHz band: 50
Ω
, 18 dB minimum return loss (21 dB typical)
1950-2250 MHz band: 17dB minimum
50-180 MHz band: 50
Ω , or 75 Ω 16 dB minimum return loss (18 dB typical)
Output connector 950-2250 MHz band: Type N female
50-180 MHz band: BNC female
Clocking options Internal, ±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 need not be
identical
External Clock
G.703 Clock Extension mode – internal ST clock can be slaved to an external T1 or E1 G.703
signal, and a G.703 timing signal re-constituted at the distant end of the link, regardless of the
actual link data rate
External TX Carrier Off By TTL 'low' signal or external contact closure - hardware function automatically over-rides
processor
BUC Reference (10
MHz):
Phase Noise
On center conductor of L-Band output connector; 10.0 MHz
±
0.06 ppm (internal reference
selected)
0.0 dBm,
±
3 dB; programmable ON/OFF
Source: either Internal Modem Reference or External Reference (10 MHz)
dB/Hz Frequency Offset
-105
10 Hz
-125 100 Hz
-138 1 kHz
-148 10 kHz
-150 100 kHz