Comtech EF Data C5 - Manual (Page 171)

C5/K1/K3 Integrated Satellite Terminal System Operation
Rev. 0 4–45
4.1.3.11.1 Utility Modulator
Refer to Figure 4-15.
UTILITY Displays single code/data rate modems only.
If CR/DR is blank, [ENTER] CR: ____ code and data rate one time.
If CR/DR is displayed, DR: _____ KB, then fixed code/data rate is
shown.
ASSIGN TRANSMIT
FILTERS Transmit filter display/assignment utility. Used to make filter rate
re-assignments. The modulator has five symbol rate filter presets
designated as A, B, C, D, and V.
Code Rate Data Rate Range
BPSK 1/2 2.4 to 1250 kbit/s
QPSK 1/2 4.8 to 2500 kbit/s
QPSK 3/4 7.2 to 3750 kbit/s
QPSK 7/8 8.4 to 4375 kbit/s
Notes:
1. Maximum Symbol Rate: 2500 kbit/s
2. Maximum Data Rate for Low Var. Rate: 512 kbit/s
3. Switching between modem type resets the filter presets to
their factory defined values. Refer to Figure 4-15 for other
code rates assigned to the modem.
To change a preset assignment, press [ENTER] when the data for
that preset is displayed. Press [
"] or [#] until the flashing cursor is
at the parameter to be changed, then [
$] or [%] to change that
parameter. After all changes have been made, press [ENTER] to
confirm the assignment. If a preset data/code rate is changed and the
modem is currently using that preset, the modem will be
reprogrammed to the new data/code rate.
MODULATOR TYPE Transmit filter type select. Select EFD CLOSED, CSC CLOSED, or
FDC CLOSED network filtering.
Upon entry, the operational status may be changed. Press [
$] or [%]
to make the selection. Press [ENTER] to execute the change.
Note: TX filter type is selectable only when CUSTOM is selected
for the modem type in the Utility Modem Type menu.
ENCODER TYPE Encoder type selection. Select Viterbi or Sequential encoder type.
Upon entry, the operational status may be changed. Press [
$] or [%]
to make the selection. Press [ENTER] to execute the change.
TX BPSK ORDERING Transmit BPSK bit ordering selection. Select STANDARD or
NON-STANDARD.
Upon entry, the operational status may be changed. Press [
$] or [%]
to make the selection. Press [ENTER] to execute the change.
MOD SPECTRUM Programmable vector rotation allows the operator to select Normal
or Inverted (INVERT) for spectrum reversal of the I and Q baseband
channels.
Upon entry, the operational status may be changed. Press [
$] or [%]
to make the selection. Press [ENTER] to execute the change.