Sea Tel DAC-2202, Installation And Operation Manual

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Setup DAC-2202 Antenna Control Unit
5-4
Continue with Azimuth trim, then re-target the satellite several times to verify that targeting is now driving the
antenna to a position that is /- 1.0 degrees of where the satellite signal is located.
5.8. AZ TRIM
Azimuth trim offset parameter is entered in tenths of degrees. Offsets true azimuth angle display to compensate for
installation alignment errors when used with Ships Gyro Compass input reference.
Azimuth Trim does not affect
REL azimuth reading . Increase number to increase displayed value. Refer to “Optimizing Targeting” in the Setup
section of your antenna manual.
To update: While in the AZ TRIM sub-menu, press the LEFT arrow key to bring the cursor under the ones digit. Press
the UP or DOWN arrow key to increment or decrement the selected digit. Minus values are entered by decrementing
below zero. Use the LEFT or RIGHT arrow key to move the cursor left or right to select other characters to modify.
When you are finished modifying press ENTER to execute the new value OR press NEXT to abort and exit setup mode.
Then re-target the satellite several times to verify that targeting is now driving the antenna to a position that is within
+/- 1.0 degrees of where the satellite signal is located.
5.9. AUTO THRES
Sets offset of AGC tracking threshold above the average noise floor. Units are in A/D counts, approximately 20
counts/dB. A setting of 0 disables auto threshold, therefore, the operator would have to manually enter a threshold
value.
When AUTO THRESHOLD is enabled, the ACU automatically re-sets the AGC tracking threshold whenever the antenna
Targets (AZ, EL or SAT), Searches or Unwraps. The new AGC threshold is set to the average signal level input
(approximate background noise level)
plus the AUTO THRES offset value. EXAMPLE: If the Noise Floor off satellite is
1000 counts of AGC and Auto Threshold is set to 100, Threshold will be set to approximately 1100 after the antenna
has finished targeting, Searching or Unwrapping. If you wish to change this parameter, refer to the Setup Flowchart to
key in and save the desired value.
To change the Automatic Threshold value
OR manually set threshold; Note the Peak “on satellite” AGC value, move EL
and note the “off satellite” (Noise Floor) AGC value. Calculate the Difference between Peak AGC and Noise Floor AGC.
AUTO THRES should be set to 1/3 (to ½) of the Difference. This will usually be around 100 counts (3 dB) for a typical
antenna configuration. Changes to this parameter may be required based on carrier tracking frequency, possible
adjacent satellite, or ambient interference with desired satellite.
To manually update, press the LEFT arrow key to bring the cursor up under the least significant character. Continue to
move the cursor until the desired character to be edited is underscored (selected). Use the UP or DOWN arrow keys to
increment or decrement the selected character.
Use the LEFT or RIGHT arrow key to move the cursor left or right to select other characters to modify. When you are
finished modifying press ENTER to execute the new value OR press NEXT to abort and exit setup mode.
5.10. EL STEP SIZE
Sets elevation sensitivity for DishScan Tracking Mode . Units are in pedestal step resolution. For proper DishScan
operation this parameter
must
be set to
factory default value of 0000
. If not already set to the correct value for
your antenna, key in the value and press ENTER.
To manually update, press the LEFT arrow key to bring the cursor up under the least significant character. Continue to
move the cursor until the desired character to be edited is underscored (selected). Use the UP or DOWN arrow keys to
increment or decrement the selected character.
Use the LEFT or RIGHT arrow key to move the cursor left or right to select other characters to modify. When you are
finished modifying press ENTER to execute the new value OR press NEXT to abort and exit setup mode.
5.11. AZ STEP SIZE
Sets azimuth sensitivity for DishScan Tracking Mode . Units are in pedestal step resolution. For proper DishScan
operation this parameter must be set to factory default value of 0000 . If not already set to the correct value for
your antenna, key in the value and press ENTER.
To manually update, press the LEFT arrow key to bring the cursor up under the least significant character. Continue to
move the cursor until the desired character to be edited is underscored (selected). Use the UP or DOWN arrow keys to
increment or decrement the selected character.
Use the LEFT or RIGHT arrow key to move the cursor left or right to select other characters to modify. When you are
finished modifying press ENTER to execute the new value OR press NEXT to abort and exit setup mode.