Comtech EF Data SDM-100A - Manual (Page 52)

Operation SDM-100A Satellite Modem
3–18 Rev. 0
3.2.1.1.3 Configuration Interface
TX Clock Source Programs the clock source for the modem transmitter clock.
“TX Terrestrial” sets the TX clock to recover timing from the
incoming clock/data.
“RX (Satellite)” sets the TX clock to operate from the satellite clock.
“SCT (Internal)” sets the TX clock to operate from the modem
internal clock. This is also the fallback clock.
On entry, the current transmit clock setting is displayed. Press [
↑ ] or
[ ↓ ] to select “SCT,” “TX Terrestrial,” or “RX (Satellite)” clock. Press
[ENTER] to execute the change.
TX Clock Phase Programs Transmit Clock phase to “Auto,” “Normal,” or “Invert.”
On entry, the current setting for the TX clock phase is displayed.
Press [
↑ ] or [ ↓ ] to select “Auto,” “Normal,” or “Invert.” When “Auto” is
selected, the modem will automatically select normal or invert to
properly phase the transmit clock with the transmit data. Press
[ENTER]
to execute the change.
Buffer Clock Programs interface buffer output clock.
“RX (SATELLITE)” sets the output buffer clock to the satellite clock.
“SCT (INTERNAL)” sets the buffer clock to operate from the modem
internal clock. This is also the fallback clock.
“EXT. REFERENCE” sets this clock source to the Master Clock (or
Terminal Timing) external reference, which is received on the DATA
I/O connector on the rear of the modem.
“TX TERRESTRIAL” sets the buffer output clock to recover timing
from the incoming TX data clock.
On entry, the current setting of the interface buffer clock is displayed.
Press [
↑ ] or [ ↓ ] to select “RX (SATELLITE),” “SCT (INTERNAL),”
“EXT. REFERENCE,” or “TX TERRESTRIAL” for the buffer clock.
Press [ENTER]
to execute the change.
RX Clock Phase Programs the RX clock phase to “Normal” or “Inverted.”
On entry, the current status of the RX Clock is displayed. Press [
↑ ] or
[ ↓ ] to select “Normal” or “Invert.” Press [ENTER] to execute the
change.