Sailor 100, Руководство по обучению, установке и обслуживанию

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Removal and replacement of ADU modules
8-12 Chapter 8: Service & maintenance 98-137654-A
This module is positioned near the service switch at the bottom
of the pedestal. It converts the GPS satellite signals into current
position data.
2. Television Interface Module (TIM).
The purpose of the TIM is to interface between the ADU coaxial
cable carrying several signals (DC, modem, RX IF)
and the cable to the LNB, and the PCM. The TIM takes the
received L-band transponder signal from the LNB and forwards it
to the ACU.
For tracking purposes the TIM has a DVB-S/S2 demodulator for
tracking the TV satellites. For narrow-band signal or non-DVB
tracking the TIM also has a power detector as signal strength
indicator. The TIM also has a PSU for the external LNB.
The TIM consists of the following blocks:
• Power supply block for on board circuits, supply to PCM board
and regulated external output to LNB (with band switching).
• DVB-S/S2 tracking receiver with tuner and demodulator
including wide band signal detector and narrow band channel
detector.
• LNB Receive signal down converter with mixer and PLL.
• FPGA section to control the functions of the TIM including DVB
transport stream decoding.
• Filters for splitting and combining the DC, modem, received
down converted IF from the LNB.
3. DC-Motor Driver Module for cross elevation (DDM).
The DDM shall - based on inputs from the PCM - control the
torque delivered by the brush-less DC-motors (BLDCM), used to
control the position of the parabolic reflector.
The DDM board is:
• Communication slave of the ADU Serial-Bus (S-Bus)
connecting the DC-motor Driver Modules (DDM), the
Polarization Motor Module (PMM), the Inertial Sensor Module
(ISM) and the Pedestal Control Module (PCM).
• Connection to the BLDCM, and delivering the required phase
current to the motor.
• Decoding the HALL-sensor input from the Zero Reference
Module (ZRM).
• Decoding the input from the Optical Rotary Encoder (ORE).
• Incorporating a break function when not powered.
4. Cross elevation motor and encoder.
SAILOR100TM.book Page 12 Tuesday, January 29, 2013 2:44 PM