Scrambling types, Differential encoder, Transmit frequency (if) – Comtech EF Data SNM-1001L User Manual
Page 317: Frequency reference, Transmit frequency change time, C.2.3 scrambling types, C.2.4 differential encoder, C.2.5 transmit frequency (if), C.2.6 frequency reference, C.2.7 transmit frequency change time
SNM-1001L Satellite Modem
Revision 1
Burst Mode Modulator Operation
MN/SNM1001L.OM
C–3
C.2.3 Scrambling
Types
One of the following scrambling types can be selected by the operator.
• A programmable seed 2^15 -1 Synchronous Scrambler.
• None
C.2.4 Differential
Encoder
The differential encoder is not needed as the data inversion ambiguity is resolved during
acquisition.
C.2.5 Transmit
Frequency
(IF)
The range of the output IF spectrum can be selected by the operator from 50 to 180 MHz, in 1
Hz steps.
C.2.6 Frequency
Reference
SCT, RX Bit Clock, and IF output are locked to the Frequency Reference.
Internal (Standard
Stability over the operating temperature range =
± 10 PPM.
Internal High Stability
(Optional)
Stability over the operating temperature range =
± 0.2 PPM.
External Reference
Input (Standard)
The External frequency reference connector is located on the back panel. This
allows Frequency Reference to be locked to an external reference frequency
standard.
Impedance 75
Ω
Frequency
1, 5, 10 or 20 MHz
Amplitude
≥ +0 dBm < +20 dBm
DC offset
Capacitively coupled
Connector BNC
Reference Frequency
Output (Optional)
The External frequency reference connector can be used as an output when the
High Stability option is installed. 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 +10 dBm
± 5 dBm.
C.2.7
Transmit Frequency Change Time
The time between the end of a remote command and the end of the modem reply for frequency
change and synthesizer lock will be < 200 mS.