Sea Tel DTV04, Installation And Operation Manual

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DTV04 HD TVRO Antenna Basic System Information
3-7
3.3.1.
The Above Decks Equipment consists of an Antenna Pedestal inside a Radome assembly. The
pedestal consists of a DIRECTV Slimline antenna dish & feed with 5 circular Low Noise Block
converter (LNBFs) with a reflector skew motor mounted on a stabilized antenna pedestal. The
radome provides an environmental enclosure
for the antenna pedestal assembly inside it.
This keeps wind, water condensation and salt-
water spray off the antenna pedestal
assembly. This prevents damage and
corrosion that would shorten the expected
life span of the equipment.
Antenna ADE Assembly
The antenna control coax cable is connected
between the antenna radome assembly and
the antenna control unit. This cable provides
DC voltage to the antenna and all control
signals to and from the antenna.
Five other RG-6 (or better) coax cables are
installed from the antenna radome assembly
to the below decks equipment. These four
cables carry the intermediate frequency (950-
1450MHz for Ku-Band Converted
Frequencies, 250-750MHz and 1650-
2150MHz for Ka-Band Converted
Frequencies) signals from the antenna
assembly directly to the DIRECTV 5LNB
compatible active matrix switch as well as the DC Voltage & Tone switching from the Matrix Switch
to the LNB. The Fifth coax installed is intended as a spare.
3.3.2.
The Antenna Control Unit allows the operator to control and monitor the antenna pedestal with
dedicated function buttons, LED’s and a 2 line display. The ACU and its Terminal Mounting Strip
are normally mounted in a standard 19” equipment rack. The ACU should be mounted in the front
of the equipment rack where it is easily accessible. The Terminal Mounting Strip is normally
mounted on the rear of the equipment rack. It is recommended that the antenna control panel be
mounted near one of the Satellite Receiver locations where you can see the television screen while
you are controlling the antenna.
The Antenna Control Unit is connected to the antenna, ships Gyro Compass and to the optional
Touch Screen Controller (when included).
Antenna Control Unit
Figure 3-10 DAC-2200 Antenna Control Unit
The Antenna Control Unit (ACU) communicates via an 70/120 KHz full duplex data link with the
Pedestal Control Unit (PCU) located on the antenna. This control signal is sent up the Antenna
Control Coax cable along with the DC voltage for the antenna power. 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.
Figure 3-9 DTV04 HD Above Decks Equipment