Comtech EF Data SDM-300A, Installation And Operation Manual

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SDM-300A Satellite Modem Options
Rev. 4 A–59
A.1.7.1 G.703 Specifications
Refer to Table A-19 G.703 specifications.
Table A-19. G.703 Specifications
Parameter Specification
Primary Data Circuits Supported T1 SD, RD
E1 SD, RD
Interface Type Transformer coupled symmetrical pair
Data Rates T1 1544 kbit/s ± 100 bit/s
E1 2048 kbit/s ± 130 bit/s
Pulse Width T1 324 ± 50 Ns
E1 244 ± 25 Ns
SD Amplitude
T1 3V +0.3/-1.5V-pk into 100
Ω
E1 3V +0.3/-1.5V-pk into 120
Ω
RD Amplitude
T1 3V +0.3/-1.5V-pk into 100
Ω
E1 3V +0.3/-1.5V-pk into 120
Ω
Pulse Mask T1 G.703.2
E1 G.703. 6
Jitter Attenuation T1 G.824
E1 G.823
Line Code AMI, B8ZS, B6ZS, HDB3
A.1.8 Variable Data Rates
The basic platform modem comes with single data rate capabilities. At the time of
purchase, the customer may add optional variable data rate capabilities. If variable rate
requirements arise after the purchase of a basic platform modem, these capabilities can be
added in the field using FAST technology. The variable rate options include one of the
following:
•
Rates up to 512 kbit/s
•
Rates up to 4.375 Mbit/s