Comtech EF Data CDM-550T - Manual (Page 41)

CDM-550T Satellite Modem Revision 3
Front Panel Operation MN/CDM550T.IOM
6.2.3 SELECT: CONFIG
The sub-branches available are:
CONFIG: ALL TX RX FRAME
INTFC REMCONT MASK IMPED
ALL
This menu sub-branch permits the user to completely configure the unit,
being prompted, step by step, to make choices, or edit data. This is highly
recommended for new users, as it will clearly demonstrate all the parameters
which need to be set.
TX
(Transmit) This menu sub-branch permits the user to define, on a parameter-
by-parameter basis, the transmit configuration of the unit. These menu sub-
branches would be used if the user wished to change, for example, just the
Transmit frequency.
RX
(Receive) This menu sub-branch permits the user to define, on a parameter-
by-parameter basis, the receive configuration of the unit. These menu sub-
branches would be used if the user wished to change, for example, just the
receive data rate.
FRAME
This menu sub-branch permits the user to define if the unit should operate in
a transparent mode (no framing) or in a framed mode. In the framed mode,
an overhead of 5% is added to the rate transmitted over the satellite so that
M&C information may be passed to the distant end.
INTFC
(Interface) This menu sub-branch permits the user to define which electrical
interface type is active at the data connector.
REMCONT
(Remote Control) This menu sub-branch permits the user to define whether
the unit is being controlled locally, or remotely.
NOTE: The unit may be monitored over the remote control bus at any time.
When in Local mode, however, configuration parameters may only be
changed through the front panel. Conversely, when in Remote mode, the unit
may be monitored from the front panel, but configuration parameters may
only be changed via the remote control bus.
MASK
This menu sub-branch permits the user to mask certain traffic alarms, which
may cause problems to the user. As an example, certain multiplexers use ‘all
ones’ as an idle pattern. However, by convention, the ‘all ones’ condition is
taken to be the Alarm Indication Signal (AIS). The CDM-550T monitors for
the AIS condition, and if desired, this alarm may be masked.
IMPED
(Impedance) This menu sub-branch permits the user to define the
impedance at the IF connectors, either 50 or 75
Ω.
6–5