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1 utility modulator: type 1 operation – Comtech EF Data SDM-100A User Manual

Page 103

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SDM-100A Satellite Modem

Operation

Rev. 0

3–69

3.2.2.5.1 Utility Modulator: Type 1 Operation

Assign Transmit Filters

Transmit filter display/assignment utility. Used to make filter rate
reassignments.

The modulator has five symbol rate filter presets. Filters are
designated as A, B, C, D, and V.

Note: Switching between Modem types will reset the Filter presets
to their factory-defined values.

To view the current preset assignments, press [ENTER]

when the

“Assign Transmit Fltrs” selection is displayed from the “UTILITY
FUNCTIONS” menu.

On line 1 of the display will be “TX-A,” which indicates transmitter
filter A. Following “TX-A” on line 1 will be the code rate (1/2, 3/4, or
7/8).

On line 2 will be the data rate assigned to preset “A.” Press [

] or

[

] to see the assignments for presets B, C, D, and V (TX-B,

TX-C, TX-D, and TX-V). 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

press [

] or [

] to change that parameter. When all changes are

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.

Note: These assignments are used for the selection of “TX-R”
(Transmitter Rate) in the configuration functions menu.

Modulator Type

Transmit Filter Type Select.

Allows operator to select SDM-51 compatible, CSC Closed, FDC
closed, or EFD Closed network filtering.