Comtech EF Data SDM-9000 - Manual (Page 86)

Operation SDM-9000 Satellite Modem
4–12 Rev. 4
BER THRESHOLD This function is used to set the BER threshold. If the BER
threshold set is exceeded, an RX fault will be indicated by the
modem status indicators. BER threshold may be set from 1.0
-3
to 1.0 -8 , or may be disabled by specifying NONE.
On entry, the current setting of the BER threshold is displayed.
Press [
↑
] or [
↓
] to select the desired setting. Press [ENTER] to
execute the change.
SWEEP RANGE Programs the overall travel of the sweep width range during
acquisition in the directed sweep mode. The sweep width may
be set from 0 to 120000 Hz. When set at 120000 Hz, the
modem is in the normal acquisition mode.
Upon entry, the current programmed setting is displayed. Press
[
←
] or [
→
] to move the flashing cursor. Press [
↑
] or [
↓
] to
increment or decrement the digit at the flashing cursor. Press
[ENTER] to execute the change. The smaller the range, the
faster the modem will lock, provided the RX carrier center
frequency is within the RX IF frequency sweep range.
RS DECODER Programs the Reed-Solomon decoder ON,
CORRECTION_OFF, or OFF.
On entry, the current status of the Reed-Solomon decoder is
displayed. Press [
←
] or [
→
] to select one of the following
modes:
•
ON
•
CORRECTION_OFF
•
OFF
Press [ENTER] to execute the change.
OFF Mode:
The RS decoder is normally disabled (OFF position). To
execute any of the Reed-Solomon decoder modes, enter the
desired Reed-Solomon decoder and select the desired mode.
Correction OFF Mode:
This mode turns OFF the Reed-Solomon decoder data error
correction circuitry. Data flow is then routed through normal
data paths without error corrections.
ON Mode:
The ON mode enables the Reed-Solomon decoder to provide
data error corrections.
Note: With the Reed-Solomon decoder turned ON (not OFF or
CORRECTION_OFF), the corrected BER will be reported from
the outer decoder (Reed-Solomon decoder).