Comtech EF Data SDM-300A - Manual (Page 266)

SDM-300A Satellite Modem Revision 6
Open Network Operations MN/SDM300A.IOM
10–10
10.3.1 IDR Specifications
Table 10-3. IDR Specifications
Primary Data Rates Supported
G.703 1544 kbps
2048 kbps
Engineering Service Channel
ESC Audio 2 channels at 32 kbps duplex ADPCM channel
ESC Data (Optional) 64 kbps duplex data (in place of audio channels)
Audio Encoding CCITT G.721
Audio Interface Type 600 Ω transformer balanced 4-wire
Audio Input Level -20 to +10 dBm for 0 dBm, 1 dB steps
Audio Output Level -20 to +10 dBm for 0 dBm, 1 dB steps
Filtering Internal 300 to 3400 Hz, input and output
ESC Data Interface Type EIA-422
ESC Data Rate 8 kbps
ESC Data Circuits Supported SD, ST, RD, RT, Octet in, Octet out
Data Signal Phasing Per EIA-449, data changes on the rising clock transition, is
sampled on the falling clock edge
Octet Clock Pulse Octet high in with every 8th bit, aligns with frame bit d8
Faults and Alarms
Backward Alarms Supported 4 input, 4 output
Backward Alarm Inputs 1 k Ω pull up to +5V, set below 2V to clear
Backward Alarm Outputs Form C Relay, NO, NC, C
Demodulator Fault Relay NO, C contacts available for backward alarm inputs
Deferred Maintenance Alarm Open collector, high impedance IF fault, 15V maximum, 20 mA
maximum
Note: A 64 kbps data channel may be substituted for the two audio channels.