Sea Tel ST94-21 Installation And Operation Manual Download

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Setup – Searching

ST94-21 C/Ku-Band TVRO

9-4

9.2.

Changing the Search Parameters

The information above described what some of these parameters need to be set to for a specific search pattern.

Below are some additional pieces of information on the other parameters and the steps to change any one of these
parameters.

9.2.1.

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 (any value between 1-255), the ACU automatically re-sets the AGC
tracking threshold whenever the antenna Targets (AZ, EL or SAT) or Searches. 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 or Searching.
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.

9.2.2.

EL STEP SIZE

For proper DishScan® operation this parameter

must

be set to factory default value of 0000.

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.

9.2.3.

AZ STEP SIZE

For proper DishScan® operation this parameter

must

be set to factory default value of 0000.

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.

9.2.4.

STEP INTEGRAL

For proper DishScan® operation this parameter

must

be set to factory default value of 0000.

To manually update, press the LEFT arrow key to bring the cursor 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.

EAR Controlled - ECCN EAR99