Comtech EF Data SDM-9000 Installation And Operation Manual page 153

SDM-9000 Satellite Modem
The buffer clock source selection must fall within the following parameters:
TX Terrestrial
RX Satellite
External Clock
Internal Clock
TX Terrestrial
RX Satellite
External Clock
Internal Clock
TX Terrestrial
RX Satellite
External Clock
Internal Clock
Note: G.703 interfaces have the option of HDB3 or B3ZS line coding data to the
terrestrial interface. This selection shall be made by the user.
Rev.4
G.703 Interface
No restrictions.
No restrictions.
Must be in the range from 1.544 to 20 MHz, in 8 kHz steps, or at the RX
terrestrial data rate.
No restrictions.
ECL Interface
TX and RX terrestrial clocks (data rates) must be divisible by 8 kHz, or the
TX data rate must be the same as the RX data rate.
No restrictions.
The external clock must be in the range from 1.544 to 20 MHz, in 8 kHz
steps, and the RX (data rate) clock must be divisible by 8 kHz.
Additionally, the external clock may be at the RX (data) clock rate.
Refer to "TX Terrestrial." This clock is at the same frequency as the TX
terrestrial clock.
MIL-STD-188 Interface
TX and RX terrestrial clocks (data rates) must be divisible by 8 kHz, or the
transmit data rate must be the same as the receive data rate.
No restrictions.
The external clock must be in the range from 1.544 to 20 MHz, in 8 kHz
steps, and the RX (data rate) clock must be divisible by 8 kHz.
Additionally, the external clock may be at the RX (data) clock rate.
Refer to "TX Terrestrial." This clock is at the same frequency as the TX
terrestrial clock.
Theory of Operation
5–25