Sea Tel DAC-03, Инструкция по установке и эксплуатации

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DAC-03 Tracking Antenna Controller Introduction
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1. Introduction
This manual describes the Sea Tel Model DAC-03 shipboard Tracking Antenna Control Unit (ACU). System
information, installation, setup, operating instructions, functional testing and maintenance for the ACU are also
contained herein.
This ACU allows you to control the antenna that it is connected to. It also allows you to connect your Gyro
Compass to provide heading input to the system for accurate targeting of satellites.
1.1. Characteristics
The Antenna Control Unit (ACU) communicates via an RS422 serial data link with the Pedestal Control Unit
(PCU) located on the antenna. For unlimited azimuth pedestals, the RS422 link is coupled to the PCU via RF
Multiplexers and is conducted across one of the ADE/BDE coaxial cables. The Pedestal Control Unit
stabilizes the antenna against the ship's roll, pitch, and turning motions. The ACU is the operator interface
to the PCU and provides the user with a choice of positioning commands to point the antenna, search
commands to find the satellite signal and tracking functions to maintain optimum pointing.
1.2. DAC-03 Functional Description
The DAC-03 is housed in a standard 19-inch rack mount enclosure. The front panel contains a row of
function keys used to select the desired information to be displayed and an array of numeric data entry keys
for changing parameters or commanding the antenna functions. Data is displayed on a bright 40 character
Vacuum Fluorescent display making it easy to read in all ambient light conditions. The DAC-03 can be
mounted on chassis slides allowing easy access to all internal electronics. All external connections are
brought out through three D-Subminiature connectors mounted on the rear panel. Flexible ribbon cable
extends these connections to a terminal-mounting strip mounted on the rear of the rack enclosure
separating the ship wiring from the Antenna Control Unit.
The DAC-03 uses a shipboard gyrocompass as the long-term azimuth reference. It accepts gyro compass
input from Step-By-Step OR 1:1, 36:1, 90:1 or 360:1 Synchro OR NMEA serial interface.
The DAC-03 automatically calculates the Elevation, Azimuth and Polarization pointing angles based on the
ships Latitude, Longitude and the desired Satellite Longitude position. A programmable pattern search will
automatically scan the area for a desired satellite if no signal is found. These two features make locating a
new satellite very easy.
A serial communications Monitor and Control (M&C) interface allows external control of the DAC-03 from a
PC, ASCII terminal, or telephone modem. This interface can also be used to update the ships Latitude and
Longitude information from a GPS or update heading from a gyro using the NMEA interface standard.
The DAC-03 requires satellite signal input to its internal Satellite ID Tracking Receiver to keep the antenna
peaked on satellite. This internal receiver is a DVB compliant DSS compatible Satellite Identification
receiver. Its input allows full coverage wide L-Band (950 to 2150 MHz) for tracking video transponders in all
TVRO satellites and may be set to Single Channel Per Carrier (SCPC), or Narrow Band IF (NBIF) mode to
allow tracking an L-BAND satellite beacon or narrow band data carrier.
1.3. Keyboard Entry
The keyboard entry and operation is very simple and straightforward. Pressing any of the 4 function keys
located below the VF display, enables the display of all the information associated with that function.
Please refer to the Operation section of this manual for more information.
1.4. Status LEDS
There are 4 status indicator LEDs on the front panel. They give the operator a continuous display of the
major operating states of the Antenna Control Unit. Please refer to the Operation section of this manual for
the function of each LED.