Comtech EF Data SNM-1001L - Manual (Page 245)

SNM-1001L Satellite Modem Revision 1
Specifications MN/SNM1001L.IOM
A–7
A.5.3 Scrambling Types
When scrambling is enabled, it is applied to the modulator data according to the
programmed modulator type as listed in the following table. When scrambling is disabled,
no scrambling is applied to the modulator data.
Table A-6. Scrambling Types
Modulation Type FEC or Framing Scrambling
EFD Closed,
CSC Closed Sequential ITU V.35
EFD Closed,
CSC Closed,
FDC Closed Viterbi ITU V.35 Intelsat Modified
EFD Closed Viterbi/RS Concatenated EFD Modified V.35
EFD Closed Turbo 2 12-1 Synchronous
FDC Closed Sequential FDC Modified V.35
A.5.4 Modulator Frequency Reference
SCT, RX Bit Clock, and IF output are locked to the Frequency Reference.
Internal (Standard) Stability over the operating temperature range = ± 0.02 PPM.
External Reference
Input (Standard)
The External frequency reference connector is located on the back panel. This allows the
Frequency Reference to be locked to an external reference frequency standard.
Impedance 75
Ω
Frequency 1, 5, 10 or 20 MHz (10 MHz required if supplying 10 MHz reference to BUC or
LNB)
Amplitude
≥ +0 dBm < +20 dBm
DC offset Capacitively coupled
Connector BNC female (50
Ω)
Reference Frequency
Output The External frequency reference connector can be used as an output. When selected
from the front panel, this output can be used to lock other equipment to the Internal High
Stability Reference of the selected modem.
The output is 10 MHz, the level is +5
± 5 dBm.
Calibration Front panel programmable adjustment for aging.