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Comtech EF Data SDM-309B User Manual

Page 234

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SDM-309B Satellite Modem

External Channel Unit

MN/U-SDM309B Rev. #

C-C–27

Assign TX_Fltrs: Modulator Symbol Rate
Assignment

The modulator has four symbol rate filters. Each
filter is for a specific symbol rate. The data rate
and coder rate for each filter must be established
upon initial modulator installation and when
circumstances indicate the need to do so. Filters
are designated as A, B, C, and D.

To view the current filter assignments press the
“ENTER” key when the “Assign TX_Fltrs” selection
is displayed from the utility functions menu. On
line one of the display will be TXA” which indicates
transmitter filter A. Following “TXA” on line one will
be the coder rate (1/2, 3/4, or 7/8) and on line two
will be the data rate assigned to filter “A”. Use the
right and left arrow keys to see the assignments
for filters “B”, “C”, and “D” (TXB, TXC, and TXD).

If it is desired to change a filter assignment press
the “ENTER” key when the data for that filter is
displayed. Use the right and left arrow keys until
the flashing cursor is at the parameter to be
changed. Then use the up and down arrow keys
to change that parameter. When all changes are
made press the “ENTER” key to confirm the
assignment. * Note: These assignments are
used for the selection of “TXR” (Transmitter Rate)
in the configuration functions menu.

Assign RX_Fltrs - Demodulator Symbol
Rate Assignment

Refer to the previous text under “Assign TX_Fltrs”.
The receive filters assignments are basically
identical.