System information

DAC-2202 Antenna Control Unit Operation
2-5
2.5.2. Satellite Information Menus.
Display Meaning
SAT 101 W THRS 1234
FREQ 1100 NID 1234
Press the NEXT key until the main Satellite menu is displayed. This is the
display of the current Satellite tracking information.
NID value displayed is the Network ID which is currently being received
from the satellite that the antenna is pointed to. If your ACU has an L-Band
SCPC receiver in it, “ABCD” will be displayed here. If your ACU has a 70,
or 140, MHz SCPC narrow band receiver in it, 0000 will always be shown.
SAT 101.0 W
Press ENTER to access the Satellite Longitude sub-menu. Satellite
longitude is used to calculate antenna Elevation, Azimuth and Polarity
pointing angles from the ships current location and heading.
To manually update, press the LEFT or RIGHT arrow key to bring the cursor
up under the tenths digit to the left, or the E/W character to the right
respectively. 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.
Range of acceptable latitude values is 000.0 East to 180.0 East/West to
000.0 West, however longitude may be entered as 000.0-359.9 East if you
prefer (181.0 East is the same as 179.0 West). Tenths may be entered
(and will be used internally) but the display will round off to nearest whole
degree.
When the hemisphere character is selected press the UP or the DOWN
key to toggle East/West hemisphere.
Press ENTER to target the displayed satellite position OR Press NEXT to
abort and return to the main Satellite menu.
THRS 1234
Press DOWN or ENTER to access the Threshold sub-menu. Threshold is
a minimum AGC value for the ACU to determine if satellite signal has been
located or has been lost.
Default setup is Automatic Threshold, which sets the Threshold value to
nnnn counts of AGC above the average off satellite AGC value whenever
the ACU Searches, Targets or Unwraps (refer to your antenna manual for
the default setting for AUTO THRES parameter).
To manually set threshold; Note the Peak “on satellite” AGC value, move
AZ or EL and note the “off satellite” (Noise Floor) AGC value. Calculate the
difference between Peak AGC and Noise Floor AGC. Threshold should be
set to 1/3 (to ½) of the Difference above Noise Floor.