Sailor Inmarsat B Workshop Manual

accompanying documentation is disclaimed. The information in this manual is furnished for informational use only, is subject to change without notice, may contain errors or inaccuracies, and represents no commitment whatsoever. This agreement is governed by the laws of Denmark. Doc.no.: W4400GB0 Issue: D/9936

2-1 2.2 BELOW DECK EQUIPMENT 2-6 3 MODULE DESCRIPTION 3-1 3.1 ABOVE DECK EQUIPMENT 3-1 3.2 BELOW DECK EQUIPMENT 3-16 4 ACCESSORIES 4-1 4.1 SC4350 CONTROL UNIT 4-1 4.2 SD4360 DISTRESS BUTTON 4-1 4.3 H4394/95 VERITAS CONNECTION BOX 4-2 4.4 H4396 T-CONNECTION BOX 4-2 5 DISASSEMBLING, CONNECTORS, MODULE AND SOFTWARE LOCATION 5-1 5.1 ANTENNA UNIT 5-1 5.2 TRANSCEIVER UNIT 5-17 5.3 HANDSET 5-25 5.4 CONTROL UNIT 5-25 6 SERVICE INTERFACE 6-1 6.1 ADE 6-2 6.2 ALARM 6-4 6.3 BOOK 6-4 6.4 BUTTONS 6-5 6.5 CAN 6-5 6.6 CASC 6-5 6.7 COURSE 6-7 6.8 CU 6-7 6.9 DATE 6-9 6.10 EXIT 6-10 6.11 GYRO 6-10 6.12 HELP 6-10 6.13 LES 6-11 6.14 LOG 6-11 6.15 MODEM 6-12 6.16 NUMERIC 6-13 6.17 PAX 6-13 6.18 POSITION 6-14 6.19 PRINTER 6-14 6.20 REGION 6-15 6.21 REMARK 6-16 6.22 SES 6-16 6.23 SNU 6-17 Inmarsat B

7-3 7.9 DISTRESS BUTTON 2 7-3 7.10 TELEX INPUT 7-3 7.11 PRINTER INPUT 7-4 7.12 ADE INPUT 7-4 7.13 NMEA POSITION INPUT 7-5 7.14 SERVICE INPUT 7-5 7.15 NMEA GYRO INPUT 7-5 7.16 PRINTER ON-LINE 7-6 7.17 HEADING KNOWN 7-6 7.18 POSITION KNOWN 7-6 7.19 OCEAN REGION VALID 7-7 7.20 CONTROL UNIT FOUND 7-7 7.21 SCANBUS DATA TRANSMISSION 7-7 7.22 SCANBUS DATA RECEPTION 7-7 7.23 TU BUS 7-8 7.24 MODEM FOUND 7-8 7.25 MODEM ACTIVE 7-8 7.26 MODEM RX SU RATIO 7-9 7.27 SPS FOUND 7-9 7.28 SPS RX IF 7-9 7.29 SPS RX FILTER 7-9 7.30 SPS TX IF 7-10 7.31 SPS TX FILTER 7-10 7.32 SPS DSP 7-10 7.33 SPS OCXO 7-11 7.34 SPS RX S/N RATIO 7-11 7.35 ADE FOUND 7-11 7.36 DOWN CONVERTER LOCKED 7-12 7.37 TRACKING RECEIVER LOCKED 7-12 7.38 UP CONVERTER LOCKED 7-12 7.39 HPA FAILED 7-13 7.40 HPA TIMED OUT 7-13 7.41 HPA STOPPED 7-13 7.42 ADE READY 7-14 9936

7-15 7.46 ADE ELEVATION RATE SENSOR 7-15 7.47 ADE CROSS-ELEVATION RATE SENSOR 7-15 7.48 ADE INCLINOMETER 7-16 7.49 ADE CONNECTION STABILITY 7-16 7.50 VDP RUNNING 7-17 7.51 VDP MODEM DETECTED 7-17 7.52 VDP CLOCK DETECTED 7-17 7.53 PAX FOUND 7-18 7.54 PAX RUNNING 7-18 7.55 PAX PHONE 1 ACTIVITY 7-18 7.56 PAX PHONE 2 ACTIVITY 7-19 7.57 PAX PHONE 1 PABX SETTING 7-19 7.58 PAX PHONE 2 PABX SETTING 7-19 7.59 PAX PHONE 1 LINE NOISE 7-20 7.60 PAX PHONE 2 LINE NOISE 7-20 7.61 SPS OCXO WARM 7-20 7.62 ADE FAILED 7-21 7.63 ADE CONTROL INPUT 7-21 7.64 ADE CONTROL OUTPUT 7-21 8 PERFORMANCE CHECK AFTER REPAIR 8-1 8.1 START-UP SEQUENCE 8-1 9 SERVICE 9-1 9.1 CHECK OF OCXO 9-1 10 PARTS LISTS 10-1 11 ABBREVIATIONS 11-1

to provide the service technician with the knowledge about the system needed to locate faults and carry out repair and performance checks after repair. The contents of this manual have been structured as follows. This chapter contains a brief description of the units of which a terminal consists, including accessories. At the end of this chapter, technical specifications are listed. Chapter 2 describes the system concept concerning antenna platform, its stabilisation and RF signal path and finally the transceiver unit. Chapter 3 is a technical description of the modules of which the antenna and transceiver unit consist. Chapter 4 is a technical description of the accessories. Chapter 5 concerns disassembling, connectors, module and software location. Chapter 6 is a description of the commands in the service interface program, a software program which is helpful during installation and trouble shooting. Chapter 7 is a more detailed description of the self-test command and its use in locating faults. Chapter 8 concerns performance checks after repair. Chapter 9 describes preventive maintenance and how to adjust the system reference oscillator. Chapter 10 contains the parts lists. Chapter 11 is a list of the abbreviations used in this manual. Note: All descriptions of the ADE especially the ADE search are valid from ADE/TSP SW version 2.3.0 only.

shows an installation with the various types of accessories. ADE: The ADE (Above Deck Equipment) consists of a stabilised platform pointing the antenna towards the satellite independent of the motion of the ship. Besides the stabilisation including motors, sensors, tracking and stabilisation processor, the platform also contains the main part of the RF equipment. BDE: In the BDE (Below Deck Equipment) are placed the first/last part of the transmitter/ receiver consisting of a baseband UP and DOWN converter. Besides the interface circuits for the various types of externally connected equipment, the BDE also contains the signal processing, i.e. error correcting coding/decoding, voice coding/ decoding etc. Handset: The control handset SC4345 is an integrated handset with display and keyboard used when a voice call is in progress. A call is set up by entering the phone number from the handset keyboard. A voice distress call can be started by removing the handset from the hook and activating the distress button placed in the hook. Another function of the handset is to use it as a control and set-up unit, where functions like the selection of coast station and satellite can be carried out. Control unit: The control unit SC4350 is a desk/bulkhead mounted keyboard and display with an additional handset without keyboard and display. Distress button: The distress button can be used to activate a voice or a telex distress alert. The kind of distress alert the button is used for is selected during installation. Connection box: If there is a need for the connection of more than one handset or control unit, the connection box is used. A maximum of five handsets or control units can be connected to one transceiver unit which is possible by using four connection boxes. Veritas: The Veritas connection box can be used as an interconnection box between the transceiver unit and other system units using ship installation cables. Cables of that type cannot be connected directly to the relatively small SUB-D connectors at the rear panel of the transceiver unit. Inside the Veritas connection box, to interface with ship installation cables, there is a single printed circuit board containing SUB-D connectors to interface with the transceiver unit and wire terminal blocks. Besides interfacing between transceiver unit and ship installations, a gyro repeater is also included. The gyro repeater can be used if there is no NMEA signal from the gyro of the ship.

PABX Connection or Push Button Telephone 32213E Gyro NMEA GPS NMEA PABX Heading Information 56/64 Kbit/sec. Async./Sync. Position Information Personal Computer Heading Information or Gyro Distress Key SD4360 Transceiver ST4425 Power Cable DC 24V Compass Keyboard Telex H1640 Maritime Computer Connection H4396 Box Local Net Matrix Printer H1252 Control Unit SC4350 ABOVE DECK BELOW DECK SC4345 Control Handset SAT-B Antenna SA4415 Fascimile (G3) Veritas H4394/95 Connection Box SAT-B Transceiver ST4425C can be replaced by Control Unit All Control Handsets SC4345 SC4350 and vice versa. Optional Converter Hard Disk On / Off

normal tuning range, designed according to Inmarsat B System Definition Manual and GMDSS requirements. Configuration: SAT-B antenna SA4415 SAT-B transceiver, 24V ST4425 B/C Control handset SC4345 Control unit, desk/bulkhead SC4350 Distress key SP4360 Interconnection: SAT-B antenna (ADE) to SAT-B transceiver (BDE): Single coaxial cable (RG 214) up to 100 m carrying Rx/Tx IF signals (21.4/62.9 MHz), data (4.8 kbit/s half duplex), 40.32 MHz reference signal and ADE power (40V DC). SAT-B transceiver (BDE) to control handset and/or control units: Multiconductor cable (8*0.25 mm2 + screen) up to 300 m implementing Scanbus interface (LAN 76.8 kbit/s, ISOOSI 1-4), audio (Rx/Tx audio signal, 0 dBm) and power (24V DC). Services: Telephony incl. echo cancellation and DTMF signalling (APC vocoder, 16 kbit/s). Telex (ITA-2, 50 baud). Data communication (Hayes compatible (AT), 9.6 kbit/s). Facsimile (CCITT group 3, 9.6 kbit/s). Optional: High speed data communication (56/64 kbit/s), All modes available as duplex and fixed-originated simplex. External I/F: Scanbus: (DB-9 connector) Connection of control unit. NMEA: (DB-9 connector) Connection of 2-wire NMEA to GPS and GYRO. DATA: (DB-9 connector) Connection of personal computer. 1 asynchronous serial (high speed) DTE/DCE port (9.6, 56, 64 kbit/s) according to CCITT Rec. V.11 and X.27. PC/Printer: (DB-15 connector) Connection of personal computer and printer. 1 asynchronous serial DTE/DCE port (50 baud telex and 9.6 kbit/s data) according to CCITT Rec.V.24. 1 asynchronous serial DTE/DCE port (printer) according to CCITT Rec. V24. Alarm: (DB-15 connector) Connection of alarm unit and alarm indicating unit. Phone1: (RJ-11 connector) 2W phone/PABX/FAX interface. Phone2: (RJ-11 connector) 2W phone/PABX/FAX interface. Antenna: Parabolic dish antenna for RHCP signals (21 dBi gain) with active stabilisation on 3 axes (azimuth, elevation and cross elevation) using rate sensors, inclinometers, and signal strength tracking. Transmission: 1626.5 - 1646.5 MHz (normal maritime tuning range, 20 kHz channel spacing for voice communication). EIRP = 25, 29, 33 dBW. Reception: 1525 - 1545 MHz (normal maritime tuning range, 20 kHz channel spacing for voice communication). G/T = -4 dB/K. Modulation: TX 24,132 kbit/s O-QPSK RX 6 kbit/s BPSK, 24/132 kbit/s O-QPSK. Coding: FEC convolution coding and 8 level soft decision Viterbi decoding (k = 7) and (R = 1/2 , 3/4). For high speed data, a sequential decoder with k = 36 and R = 1/2 is used. Power Supply: Supply voltage: 24V DC +30/-10%. Power consumption: TX/RX =250/120W Environments: SAT-B antenna: Temperature range: -25 to +55 °C. SAT-B transceiver: Temperature range: -15 to +55 °C. Roll, pitch and yaw: ± 30° (T = 8 s), ± 10° (T = 6 s), ± 8° (T = 50 s) Turning rate: ± 6 deg/s Size and weight: SAT-B antenna: H*W = 1410 mm * 1250 mm M = 129 kg. SAT-B transceiver: H*W*D = 132 mm * 370 mm * 267 mm M = 8.7 kg Control handset: H*L*B = 67 mm * 219 mm ‘ 70 mm M = 1.2 kg Control unit: H*B*D = 100 mm * 200 mm * 120 mm M = 0.8 kg

2-1 2.1.1 PRINCIPLE OF STABILISATION 2-2 2.1.2 COMPONENTS OF THE STABILISATION SYSTEM 2-3 2.1.3 ANTENNA BEHAVIOUR DURING START-UP SEQUENCE 2-4 2.1.4 ANTENNA BEHAVIOUR DURING GLOBAL SEARCH 2-4 2.1.5 ANTENNA BEHAVIOUR DURING REGION SHIFT SEARCH 2-4 2.1.6 TRACKING ALGORITHM 2-5 2.1.7 COMMUNICATION, SETUP AND STATUS SURVEILLANCE 2-5 2.2 BELOW DECK EQUIPMENT 2-6 9936 Inmarsat B

(ADE) consists of two parts, one concerning the RF and one about the stabilisation. The other main part of the terminal is the transceiver unit. 2.1 ABOVE DECK EQUIPMENT The block diagram shown in fig. 2.1 concerns the RF part of the antenna unit. 35522A Synthesizer Tracking Receiver Converter Down Synthesizer LNA HPA Diplexer Converter Up Triplexer Conn. Board SMPS Rotary Joint TSP Sensor Block Motors DMB Transmitter Level Power Control Voltage Serial Comm. to SMPS Signal Strength Data RX/TX Filter selc. Frequency Selc. 21.4 MHz RX 10.08 MHz ref. 62.9 MHz TX DMB To Transceiver Unit Fig. 2.1. The RF part consists of a transmitter and a receiver part sharing a single antenna. The diplexer separates transmitter and receiver signals to allow full duplex transmission without transmitter degrading receiver performance. The transmitter part consists of an UP converter which mixes a fixed intermediate frequency signal to a signal in the transmitter band (1.6265 - 1.6465 GHz). The frequency selection is made by means of the UP converter synthesizer. In the HPA (high power amplifier) the low level signal from the UP converter is amplified before it enters the diplexer and antenna. The receiver part consists of an LNA (low noise amplifier) and two receiver units, a DOWN converter which is the counter part of the UP converter, and a tracking receiver which is a part of the tracking and stabilisation system. The output signal from LNA is split out to both units. The DOWN converter and DOWN converter synthesizer mix the receiver band (1.525-1.545 GHz) to a fixed intermediate frequency of 21.4 MHz. Due to different service types, voice, high speed data etc., different receiver bandwidths are required. In the DOWN converter three bandwidths can be selected on the final intermediate frequency. The tracking receiver is always tuned to the NCSC channel in a given ocean region. The reason this channel type is used, is that there is always a signal presented from the satellite, unlike other channel types where service activation is used. The tracking receiver can be thought of as a frequency selective power meter which measures the signal level on the channel which it is tuned to. It has its own synthesizer and covers the entire receiver band. The tracking receiver output is a direct voltage which is used as input for the tracking and stabilisation system. As described in the previous chapter, a single coax cable between transceiver unit and antenna unit is used. To make this concept work, a triplexer is used to distribute the signals from the transceiver unit to the different modules in the antenna unit and to combine the different signals from the antenna unit to a composite signal before it enters the cable. To make the transceiver unit and antenna unit work together, data communication between them is necessary. On the triplexer board a data receiver/transmitter is placed. The kind of data exchanged between

Inmarsat B PAGE 2-2 9936 antenna unit and transceiver unit is status and fail information from the antenna and configuration data. Configuration data concerns frequency set-up of the synthesizer, DOWN converter filter selection, and transmitter power level. The received data from the transceiver unit is processed by a microcontroller placed on the tracking and stabilisation processor board, which also takes care of data in the opposite direction. The tracking and stabilisation processor board is the heart of the antenna stabilisation system. To stabilise the platform, tilt sensor and rata sensors are placed in different places on the platform. Those sensors together with the tracking receiver supply input to the tracking and stabilisation processor board, which, as output, controls the motors. In the following chapter the stabilisation system is described in detail. The connection from the triplexer to the coax cable is made by means of a connection board and a rotary joint. The rotary joint is used instead of a cable unwrap system. On the connection board, the main 40V supply voltage from the transceiver unit is taken out and connected to the input of the switch mode power supply (SMPS). The SMPS delivers different kinds of supply voltages to the modules. Besides those fixed voltages, a microprocessor controlled voltage used to regulate the output power from the HPA is also delivered. If for some reason signals between transceiver unit and antenna unit are missing, a signal called dead man’s button is activated, shutting the regulated voltage to the HPA, thus preventing the HPA from transmitting. 2.1.1 PRINCIPLE OF STABILISATION The main objective of the stabilisation system is to keep the antenna pointing as accurately as possible in the referenced pointing direction at any time under environmental conditions (ship yaw, pitch and roll). To obtain this the antenna stabilisation system is based on three axis active stabilisation with closed loop control of each axis. The individual axes are named azimuth (yaw/turning correction), cross elevation and elevation (roll and pitch correction) as shown in fig. 2.1.1. Each axis uses a double sensor principal for angular movement measurement (combined measurement of angular rate and absolute angle) and an electrical motor as actuator. The angular rate is measured by means of angular rate gyros based on oscillating piezoelectric crystals. For absolute angle reference the elevation (El) and cross elevation (Ce) axes use a fluid based inclinometer, and the azimuth (Az) axis uses the ships gyro compass. 35972B Az Ce El Fig. 2.1.1.

Inmarsat B PAGE 2-3 9936 The controller function of the stabilisation system is performed by the tracking and stabilisation processor board (TSP board). In addition to the three axes contributing to the active stabilisation (Az, El and Ce) the antenna is equipped with a horizontal axis holding a small sensor box. The sensor box holds several of the sensors for the stabilisation system. Its main function is to make it possible to keep the working point of the inclinometer sensor as close to the real horizontal level as possible under all antenna elevation reference angles. When the elevation part of the pointing reference changes, the angle between the antenna disc and the horizontal box will be changed into the same angle value in the opposite direction, thus keeping the sensor box horizontal at all times. 2.1.2 COMPONENTS OF THE STABILISATION SYSTEM Fig. 2.1.2 shows a block diagram of the stabilisation system. Az rate sensor El rate sensor Inclinometer Tracking receiver Ce rate censor Motor Driver Motor Driver Motor Driver Motor Driver Zero-mark det. Horizontal step motor El axis step motor Az axis step motor Horizontal axis DC motor Brushless TSP Controller 35973B Fig. 2.1.2. The stabilisation system can be divided into functional groups: Azimuth axis: Azimuth angular rate gyro sensor. Fluxgate compass. Ship gyro. Azimuth step motor driver. Azimuth step motor. Elevation axis: Elevation angular rate gyro sensor. Elevation inclinometer (one axis of the dual axis inclinometer unit). Elevation step motor driver. Elevation step motor. Cross elevation: Cross elevation angular rate gyro sensor. Cross elevation inclinometer (second axis of the dual axis inclinometer unit) Cross elevation bldc motor driver. Cross elevation bldc motor. Horizontal axis: Horizontal axis zero mark detector (optical fork). Horizontal axis step motor driver. Horizontal axis step motor.

Inmarsat B PAGE 2-4 9936 2.1.3 ANTENNA BEHAVIOUR DURING START-UP SEQUENCE When the complete system, or just the ADE, has been reset or switched off and on, the ADE will initialize and search for the satellite. The behaviour of the antenna during this process is described in this chapter. 1. Initialization A few seconds after resetting, the horizontal axis will go to the bottom stop position. A knocking sound will be heard for a few seconds. After this the axis will go up to the optical zero sensor. Then the elevation axis will initialize in the same manner. Also from this axis a knocking sound will be heard when it is in the bottom position. When the elevation axis has returned to horizontal position, the cross-elevation axis will begin to move towards horizontal position. A high-fre- quency switch-mode sound can be heard when the cross-elevation axis moves. The antenna will be ready after 2-3 minutes. If the transceiver has received the position of the vessel, the fast search will begin. 2. Fast search The elevation axis will move up to the calculated elevation angle of the chosen satellite, and the azimuth will turn clockwise 360°. This rotation will last about 1-2 minutes. After the search, the azimuth will go to the position with the highest signal level. This rotation will last less than 1 minute. Here a fine search will be performed. 3. Fine search The fine search is a cross-shaped search, the centre of which will be in the expected direction of the satellite. The angular speed of this search is lower than the speed of the fast search. First the elevation axis will search vertically from 20° below the expected satellite position to 20° above this position. Then it will search horizontally from 15° to the left of the expected position to 15° to the right of it. Finally it will move back to the azimuth and elevation angles where the highest signal levels were measured. The fine search will last 1-2 minutes. The total start-up sequence will last 5-6 minutes. 2.1.4 ANTENNA BEHAVIOUR DURING GLOBAL SEARCH If the modem cannot achieve synchronisation on the received NCSC signal within 5 seconds after the fast search, a global search will start. In this search mode the azimuth will rotate slowly 360° clockwise, and at the same time the elevation axis will move up and down in a zigzag shape. The elevation top of this zigzag is 80° above the horizon and the elevation bottom is 5° above the horizon. After this the satellite dish is turned to the direction where the highest signal level was measured. A ± 25° horizontal and vertical fine search is performed around the direction whre the highest signal level was measured. The total global search will last between 6-7 minutes. 2.1.5 ANTENNA BEHAVIOUR DURING REGION SHIFT SEARCH The behaviour of the antenna during a region shift search depends on whether the position of the vessel is keyed in manually or received directly from a GPS. In the following description, the values in square brackets are those of a position keyed in manually, the other values are with a functional GPS connected to the system. If for some reason the signal between the satellite system and the ship is blocked by eg. a smokestack or an other object on board or ashore, it can be necessary to change to an other region. Blocking objects can cause the signal level to drop to a value where the system is still receiving from the satellite, but where the quality of the signal is too poor to perform communication. This error may occur if for instance several calls (Ship to shore) fail, or if only two LEDs are illuminated on the handset. In such cases the transceiver can be shifted to an other region, in which case a region shift search is performed.

Inmarsat B PAGE 2-5 9936 When a region shift search is performed, the satellite dish first turns to the direction 15° [45°] to the left (or right, depending on which is closer) of the expected position of the satellite. From this point it performs a horizontal search to the point 15° [45°] to the right (or left, if the start position was right) of the satellite. After this, a ± 15° horizontal and ± 20° vertical fine search is performed around the point where the highest signal strength was measured. The total region shift search will take 1-2 minutes. 2.1.6 TRACKING ALGORITHM For long term optimisation of the antenna pointing reference a step-track algorithm is included in the control system for the antenna. The basic concept of the tracking algorithm is to measure the signal level around the current centre of pointing by moving the reference in small measurement steps. At each measurement point the reference position is fixed during an averaging time which is long enough to cover one to several sea wave periods. After the averaging period the mean level is interpreted as the tracking level for that reference point. This measurement is repeated several times at equally spaced points on each side of the centre point before a decision is taken in which direction to move the centre. This procedure is repeated on the elevation and azimuth axes one at a time until a new search is started. The size of the measurement steps on the azimuth axis increases when the elevation reference angle increases. 2.1.7 COMMUNICATION, SETUP AND STATUS SURVEILLANCE In addition to antenna tracking and stabilisation the TSP controller works as the central control unit in the ADE and takes care of various setup and control tasks in the ADE. Control data communication with the BDE: Receiver, transmitter and tracking receiver channels. Search initiation and sky slice parameters. Ship gyro compass information. Transmitter power level. Antenna status information. HPA setup and error reporting: The TSP communicates with the microcontroller in the HPA unit. Power level infor- mation, burst length information and transmitter frequency range are sent to the HPA. Status information and error codes are received from the HPA and reflected to the BDE whenever needed. Synthesizer setup: The three synthesizer groups in the antenna (up converter, down converter and tracking receiver) are all programmed by the TSP with configuration and frequency information. The frequency programming parameters are calculated by the TSP based on the channel numbers received from the BDE. In addition the TSP surveys the lock signals generated by the synthesizers to detect if a synthesizer is unlocked. Unexpected unlock situations are reported to the BDE.

Inmarsat B 2.2 BELOW DECK EQUIPMENT The below deck equipment or transceiver unit as it is called consists of five printed circuit boards (modules) as shown in fig. 2.3. Pax CSP/VDP Modem SPS Rear Panel Connectors SMI SMPS 35974 Fig. 2.3. SPS board The SPS (signal path and synthesizer) board is the interface between the analogue RF parts at the antenna unit and the digital signal processing in the transceiver unit. The receiver IF of 21.4 MHz is converted to baseband, sampled and processed in a digital signal processor. The transmitter part consists of a quadrature mixer where two baseband data signals are up converted and combined to a 62.9 MHz IF signal. The baseband signals are generated in the modem module. A data receiver and transmitter for communication with the antenna unit is also placed at this board. All critical frequencies are derived from the system reference oscillator. The oscillator is a crystal oscillator built into an oven. The RF input/output to/from the SPS board is a single coax connection. Therefore, a combiner/splitter circuit is used to combine the RF signals to be sent to the antenna unit and the split-out received RF signal to the respective blocks which are to use them. Modem board The purpose of the modem board is to code data flow sent from the terminal to the satellite and decode data flow received from the satellite. Coding is used to make it possible to detect and correct bit errors, thus increasing the quality of the communication. To increase the security, data bits are scrambled. Scrambling and descrambling takes place in the modem. Data flow is transmitted/received in frames. The contents of a frame, besides the data to be transmitted or received, are bit sequences helping the modem to synchronise. The modem takes care of the frame format in both the receiver and the transmitter directions. CSP/VDP board The CSP/VDP board consists of two functionally separate parts. The CSP (control and signalling processor) is the main processor in the system and takes care of the satellite protocol, man/machine and external equipment interfaces. The VDP (voice and data processor) is a digital signal processor which handles voice coding and decoding and is the interface between modem and the PAX module for data and fax services. PAGE 2-6 9936

Inmarsat B PAGE 2-7 9936 PAX board The PAX board (phone and fax) contains hardware and software for interfacing with a fax machine and with push button telephones like a stand-alone telephone or a PABX network. The module also acts as an interface for data communication from a single terminal or a local network at transmission rates of 9.6 or 64 kbit/s (64 kbit/s only possible if high speed data is implemented). SMI board The SMI (switch mode power supply and interconnection) board contains the system power supply. From the ship, the main supply voltage of 24V DC is connected at the rear panel of the transceiver unit. And from that, the switch mode power supply generates a number of different voltages not only for the modules in the transceiver unit but also 40V DC for the antenna unit. At the rear panel of the transceiver unit, a number of connectors are placed for externally connected equipment. Those connectors are mounted on the board, from where they are connected to the respective modules by means of ribbon cables.

3-1 3.1.1 ANTENNA 3-1 3.1.2 DIPLEXER 3-2 3.1.3 LNA 3-2 3.1.4 DOWN CONVERTER 3-3 3.1.5 UP CONVERTER 3-4 3.1.6 HPA 3-4 3.1.7 TRACKING RECEIVER 3-5 3.1.8 TRIPLEXER 3-6 3.1.9 SYNTHESIZER FOR TRACKING RECEIVER 3-8 3.1.10 SYNTHESIZER FOR UP/DOWN CONVERTER 3-10 3.1.11 SWITCH MODE POWER SUPPLY 3-13 3.1.12 TSP 3-14 3.1.13 TILT SENSOR 3-15 3.2 BELOW DECK EQUIPMENT 3-16 3.2.1 SPS BOARD 3-16 3.2.2 MODEM BOARD 3-18 3.2.3 CSP/VDP BOARD 3-19 3.2.4 PAX BOARD 3-20 3.2.5 SMI BOARD 3-21 3.2.6 HANDSET 3-22 9936 Inmarsat B

placed at the antenna unit and transceiver unit. 3.1 ABOVE DECK EQUIPMENT 3.1.1 ANTENNA The antenna is a parabolic dish antenna as shown in fig. 3.1. 35971 SMA connector Sub reflector Fig. 3.1. The diameter of the parabolic reflector is 90 cm and the feeder element is placed inside the plastic tube in the focal point of the reflector. A small reflector with a diameter of 12 cm is placed at the end of the plastic tube. The feeder element is a helical antenna operating in axial mode, thus creating a wave of circular polarisation as required from Inmarsat. The wave is right handed. The helix is wrapped around a form of polystyrene. Inside the tube, a semi rigid coax cable connects the feeder element with the SMA connector at the bottom of the parabolic reflector. This connector is connected to the diplexer through a highly flexible coax cable. The following is a list of the most important antenna specifications: Antenna gain: 20.9 dBi Polarisation: Right handed circular 3 dB beam width: ± 7.5° Side lobe level: More than 20 dB below main lobe Axial ratio: Better than 2 dB Inmarsat B

Inmarsat B PAGE 3-2 9901 3.1.2 DIPLEXER When a conversation is in progress via a satellite, the transmission mode is normally duplex which means that the transmitter and receiver are active simultaneously. To prevent the HPA from overloading the LNA, an interconnection device is used, i.e. a diplexer. Fig. 3.2 shows a block diagram of the diplexer. Network Coupling TX Filter Antenna Port TX Port RX Filter RX Port 35523A Fig. 3.2. The diplexer is a mechanical device, built up as two tenth-order band-pass filters connected to a coupling network at the antenna port. The receiver path pass band is 1525 to 1545 MHz, and the transmitter path pass band is 1626.5 to 1646.5 MHz. Each filter is constructed of quarterwave resonators, the distance between them determining the coupling coefficient. The tuning capacitors are made using screws in the top cover of the diplexer. Changing the distance between a tuning screw and the resonator causes the top loading capacity to change, thus changing the resonance frequency of the resonator as well. The resonators are made of aluminium rods and the whole unit is silver plated to obtain a low insertion loss. Furthermore, the device is sealed on the outside to avoid oxidation. To obtain a low receiver noise figure, the LNA is placed in the diplexer. Interconnection between diplexer receiver port and LNA input is made by means of a short piece of semi rigid cable. At antenna and TX port, SMA connectors are used. 3.1.3 LNA The main signal path in the LNA is constructed with four transistors and two helical filters as shown in fig. 3.3. Network Matching Down Converter Tracking Receiver 1535 MHz 1535 MHz Power Divider Bias Bias Bias Bias Reg. Voltage Reg. Voltage Bjt Bjt Bjt GaAs 35524 Fig. 3.3. The semi rigid cable from the diplexer is soldered directly to the printed circuit board where it is connected to a microstrip impedance matching network. The matching network acts as interconnection between diplexer and the first gain stage to obtain a low noise figure. The first amplifier stage consists of a low noise GaAs FET whereas the remaining three stages are based on junction transistors. The two helical filters cover the maritime band, 1525 to 1545 MHz and ensure high immunity for out of band signals. After the last filter, a microstrip power divider equally divides the signal to tracking receiver and DOWN converter inputs. The LNA is supplied with +18V DC from the tracking receiver through the coax cable which also carries the RF signal. In order to minimise gain variation over the entire temperature range, active bias network is used to keep the current in each stage constant. The GaAs FET also uses a negative bias voltage which is made from the +18V supply in a DC to DC converter based on pulse width modulation.

Inmarsat B 3.1.4 DOWN CONVERTER The purpose of the DOWN converter is to convert an L-band signal to a fixed intermediate frequency of 21.4 MHz. A block diagram is shown in fig. 3.4. 20 kHz 10 kHz 100 kHz Filter Module Shift Register 21.4 MHz Data Clock Strobe Lo-1 Lo-2 35525 Fig. 3.4 Down conversion takes place in two steps. The L-band signal is mixed to a first intermediate frequency of 179.32 to 179.6325 MHz. The first IF signal is then mixed to 21.4 MHz. The reason why the first IF is not fixed is that the frequency of the L-band synthesizer steps in 315 kHz. This is done to lower the close in phase noise. From the output of the LNA, the received signal is fed directly to RF input of the first mixer. The mixer is a passive doubled balanced diode mixer with good large-signal properties. The local oscillator frequency ranges from 1345.68 to 1365.525 MHz. The signal level from the synthesizer module is 0 dBm ± 3 dB and is amplified in a MMIC to the required LO drive level of 10 dBm. To avoid power level variation of the local oscillator input of the mixer, the compression point of the amplifier is approximately 10 dBm. Before amplification takes place, the signal is filtered. The purpose of this filter is to attenuate spurious frequencies which may add to the synthesizer module oscillator signal. The first intermediate frequency consists of two double tuned band-pass filters separated by a dual gate MOS-FET amplifier. The total power gain including filter losses is approximately 8 dB. The power gain is temperature compensated by means of an NTC resistor in the bias network of the MOS-FET transistor. The final down conversion to second IF at 21.4 MHz takes place in the second. This mixer has the same properties as the first one. The second local oscillator amplifier amplifies the synthesizer signal from -20 dBm to the required level of 10 dBm. The amplifier is built up as a two stage tuned transistor amplifier with a 3 dB attenuator separating the transistors. The selectivity is formed by the tuned impedance matching networks. This amplifier also has a compression point of approximately 10 dBm. Due to the different types of services (voice, high speed data, telex etc.) different receiver bandwidths are required. In the DOWN converter it is possible to select between three different crystal filters, i.e. 10, 20 and 100 kHz. Those filters are located on another PCB together with buffer stages and filter selection circuits. The filter selection is made by means of switch diodes which are controlled by a TTL shift register. Three control signals (data, clock and strobe) to set up the shift register are supplied from the TSP board. The filter module buffer stages have two purposes, to amplify the signal and to serve as interconnection between the filter module and the main board. Finally the signal is amplified in a two stage dual gate MOS-FET amplifier, and a common collector stage takes care of the impedance matching to a 50 ohm load. All internal supply voltages (+15, -12 and 5V) are made by means of integrated voltage regulators. PAGE 3-3 9901

Inmarsat B 3.1.5 UP CONVERTER The input signal to the UP converter is mixed in two steps to cover the frequency band from 1626.5 to 1646.5 MHz. Lo-1 Lo-2 Output to HPA Input from Triplexer 62.9 MHz ATT 150 MHz 150 MHz ATT 1636.5 35526 Fig. 3.5. The input signal to the UP converter is filtered to attenuate out-of-band signals before the first frequency conversion. Between the filter and first mixer, a 3 dB attenuator is used to improve termination. The mixer is a passive double balanced diode mixer. Second IF is at 150.1 to 150.415 MHz. Second IF is built up as band-pass filter, a BJT amplifier, another band-pass filter and finally an attenuator. The amplifier is temperature compensated to minimise gain variations and includes a gain adjustment to set up the overall gain of the UP converter. The final frequency conversion to L-band takes place in the second mixer. The RF signal at the output of the mixer is filtered with a helical filter to reduce out-of-band spurious. The final amplification takes place in an MMIC. The two local oscillator signals are delivered by the UP converter synthesizer. The frequency of the first LO is 213.0025 to 213.315 MHz. To obtain the required drive level of 7 dBm to the mixer LO port is used a buffer built up with two transistors. The last stage is driven into compression to maintain a constant power level to the mixer. To minimise intermodulation products, a bandpass filter between the two transistors attenuates unwanted signals. The frequency range of the second local oscillator is 1776.915 to 1810.620 MHz. The buffer stage consists of a bandpass filter and an MMIC which is also driven into compression at a power level of 7 dBm. All internal supply voltages are +15V DC and generated by means of integrated voltage regulators. 3.1.6 HPA When mounted in the ADE, the HPA is placed in a separate, enclosed cabinet. The block diagram in fig. 3.6 shows the main parts of the HPA. Power Module M Controller DMB 1635.5 1635.5 Power Det. Senser Temp. EE-Prom Clock Data Strobe Clock Data Strobe Data +28V DC SMPS TSP Input from UP Converter Output to Diplexer Directional Coupler 35527 Fig. 3.6. PAGE 3-4 9901

Inmarsat B PAGE 3-5 9901 To reject out of band signals, a helical filter is placed at the input of the HPA. The output signal from the UP converter can vary approximately 17 dB depending on the length of the cable between BDE and ABE, temperature variations and AM fluctuations in the different digital modulation forms used. To remove variations in the signal power, the signal is amplified in a two-stage amplifier built up around two integrated amplifiers. The amplifiers are driven into compression, thus removing the power variation. A second helical filter is located after the amplifier stages to attenuate the harmonic contents of the signal. The final amplification is performed in the power amplifier, which is an integrated amplifier. The output power can be controlled by varying the +28VR DC supply voltage to the power amplifier. The power regulation facility serves two purposes: transmission at three predefined power levels and correction of each power level due to temperature variations and parameter spread of the components. From the directional coupler at the output of the HPA, a small part of the transmitter signal is taken out, and a power detector built up around a Schottky diode converts the signal to a direct voltage which is proportional to the transmitter power. The DC voltage is sampled by means of an A/D converter inside the microcontroller. A circulator at the output of the directional coupler is used to protect the power module if for some reason the transmitter power is reflected back into the power module. A sensor monitors the instantaneous temperature of the module, and its output is connected to a microcontroller. The microcontroller is connected to an A/D converter in the switch mode power supply which regulates the +28VR DC and thus the transmitter power. If for some reason a burst in burst mode transmission becomes too long, the output power or the temperature becomes too high, the microcontroller forces the switch mode power supply to shut down the +28VR DC supply voltage and thus the transmitter power. The interconnection between the microcontroller and the switch mode power supply is a serial connection. If a fail condition arises, an error code is transmitted to the TSP board, from where it is sent to the system processor in the transceiver unit. During a call, the TSP receives information concerning transmission, i.e. burst or continues mode and power level. That information is given to the microcontroller in the HPA, from where the A/D converter in the SMPS is controlled. 3.1.7 TRACKING RECEIVER The tracking receiver can be considered as an ordinary receiver whose detector delivers a direct voltage proportional to the received signal level. The input signal to the tracking receiver is taken from a power divider located at the LNA. The coax cable between LNA and the tracking receiver is also used to supply the LNA with DC power. In fig. 3.7 a block diagram is shown. Lo-1 To TSP 134 MHz 134 MHz 6 dB Lo-2 10.7 MHz ATT 10.7 MHz DC IF1 IF2 AGC Level Converter 35528 Fig. 3.7. The receiver is built up as a double conversion receiver, with a first IF of 133.96 to 134.27 MHz. The second IF is fixed at 10.7 MHz. The reason why the first IF is not fixed is that the frequency of the L-band synthesizer is changed in step of 315 kHz. This is done in order to lower close in phase noise. The DC block between tracking receiver input and first mixer adds an 18V supply voltage to the coax cable up to the LNA and makes sure that the DC voltage does not reach the mixer input. The first mixer, a double balanced diode mixer, down converts the L-band signal to first IF where two double tuned bandpass filters separated by a dual gate MOS-FET amplifier reject image frequencies. The final down conversion to 10.7 MHz is made by means of a mixer of the same type as the first one. At second

Inmarsat B PAGE 3-6 9901 IF, adjacent channel selectivity is obtained in a crystal filter. Between the mixer and crystal filter, a 6 dB attenuator is used to improve the termination impedance of the mixer IF port. Second IF consists of two integrated amplifiers of which the first has fixed and the second variable gain controlled by a DC voltage. After that a crystal filter limits the noise bandwidth before the final amplification in a two-stage transistor amplifier. A diode detector converts the IF signal to a DC voltage proportional to the signal strength. An AGC circuit ensures that the detector voltage is constant by regulating the gain of the second IF2 amplifier. The voltage regulating the gain is used as an indicator of the signal strength. When the input power for the tracking receiver changes from minimum to maximum, the AGC voltages change by approximately 0.5V. A level converter is used to give a 0-5V change for the same input power variation. This signal is connected to the TSP board. The module uses +15 and -12V supply voltages generated by integrated voltage regulators. 3.1.8 TRIPLEXER The main function of the triplexer is to combine and distribute signals in the coax cable between ADE and BDE to and from the different modules placed on the antenna unit. A block diagram of the triplexer is shown in fig. 3.8. :4 40.32 MHz 21.4 MHz 87 MHz Circuit FM-IF Slicer Data OSC. 99 MHz Vector Modulator 150 kHz 150 kHz Phase Control OSC. 150 kHz Combiner Splitter/ Converter Synthesizer 10.08 MHz to UP/Down 10.08 MHz to Tracking Receiver Synthesizer 62.9 MHz output to UP Converter 21.4 MHz input from Down Converter Data to TSP Data from TSP To Connection Board 35529 Fig. 3.8. The input block consists of a number of baluns separating the different types of signals from the BDE and combining the signals to the BDE. The different types of signal are listed below: 40.32 MHz reference signal In the BDE is placed a stable oscillator which is used to derive the reference frequencies for the synthesizers, among other things. The oscillator frequency is 10.08 MHz but is multiplied by a factor four before entering the coax cable. This signal is taken out of the combiner/splitter block and filtered in a bandpass filter with a center frequency of 40.32 MHz. The signal amplification takes place in an integrated circuit and two discrete transistors. The last transistor is a switch transistor converting the signal to a level suitable for TTL circuits. After level conversion, the frequency is divided by a factor four to obtain the original reference frequency of 10.08 MHz. The divider circuits are built up around two d-type flip-flops. The 10.08 MHz signal is now amplified and finally split out to two SMB connectors. From those connectors, the reference frequencies for the tracking receiver and UP/DOWN converter synthesizer are taken.

Inmarsat B PAGE 3-7 9905 62.9 MHz UP converter signal The transmitter signal from the BDE, which is a 62.9 MHz intermediate frequency signal, is taken out of the combiner/splitter block and is fed directly to an SMB connector where the input of the UP converter is connected. 21.4 MHz DOWN converter signal The output signal from the DOWN converter enters the triplexer board in an SMB connector and is then low-pass filtered before entering the combiner/splitter block. Data receiver/transmitter As described in the previous chapter, data communication between ADE and BDE is necessary. On the triplexer board, a complete 4800 bit/s data receiver /transmitter is placed. The data receiver/transmitter is built up as an FSK (frequency shift key) modem where a 99 MHz transmitter carrier is shifted ± 150 kHz in frequency depending on the data bit (one or zero). The receiver is based on the same principle except that the centre frequency is 87 MHz. The data receiver is built up around an integrated circuit which is a complete FM IF subsystem. The integrated circuit contains a mixer which converts the 87 MHz receiver signal to an intermediate frequency of 12 MHz. The needed local oscillator signal is taken from the 99 MHz crystal oscillator. The 12 MHz FSK modulated IF signal is demodulated in an frequency discriminator. After demodulation the signal is led to a data slicer reconstituting the data shape. The serial bit stream from the data slicer is connected to the TSP board. The data transmitter is built up around an integrated vector modulator. The modulation is generated through a 150 kHz I/Q signal, the phase of the Q signal switched 0 or 180° depending on the I signal controlled by the bit stream to be transmitted. The I and Q signals are square waves, but low-pass filters attenuate the harmonic contents to generate low distortion sine and cosine signals as vector modulator input.

Inmarsat B PAGE 3-8 9901 3.1.9 SYNTHESIZER FOR TRACKING RECEIVER The two local oscillator signals used in the tracking receiver are generated on this synthesizer module. The first local oscillator which is used to mix the receiver frequency to first IF is called L-band synthesizer and the other is called VHF synthesizer. The frequency coverage of the two synthesizers is listed below: L-band synthesizer: 1391.040 - 1410.885 MHz in steps of 315 kHz VHF synthesizer: 144.66000 - 144.97375 MHz in steps of 1.25 kHz A block diagram of the synthesizer module is shown in fig. 3.9. LOOP 1 PD :32 VCO :N :64/65 :A PD :126 VCO :N :A :20/21 :A :N :20/21 :128 PD VCO VHF L Band Lock det. LOOP 2 10.08 MHz from Triplexer To TSP from PLL Lock Signals 35530 Fig. 3.9. L-band synthesizer The L-band oscillator is based on a voltage controlled oscillator (VCO) with good close-in phase noise properties. Frequency stability is obtained using a PLL circuit where the VCO is locked to the highly stable reference frequency supplied from the triplexer board.

Inmarsat B PAGE 3-9 9901 The integrated PLL circuit contains phase detector, divider for reference frequency, divider with modulus two architecture and built in L-band prescaler with a division ratio of 64/65. The 10.08 MHz reference frequency is divided by 32 in the reference divider to obtain a frequency resolution of 315 kHz. The loop filter is an active low-pass filter built up around a low noise operational amplifier. The output signal from the VCO is amplified in two integrated L-band amplifiers (MMIC). The purpose of the amplifiers is not only to obtain the required signal level but also to isolate the frequency determining components in the VCO from the rest of the circuits. VHF synthesizer The VHF synthesizer is also based on PLL technology but because of the high frequency resolution of 1.25 kHz and demands for low phase noise, a dual loop synthesizer is used. The two loops are built up as conventional synthesizers with the exception that loop 1 contains a mixer. The reference divider in loop 1 is 126, giving a frequency resolution of 80 kHz, and for loop 2 it is 128, giving a frequency resolution of 78.75 kHz. When the divider in the feed back loop of loop 1 is incremented by 1, the output frequency of the VHF synthesizer is increased by 80 kHz. If at the same time, the divider in the feed back loop of loop 2 is reduced by one, the output frequency of the VHF synthesizer is decreased by 78.75 kHz. The resulting change of frequency at the output of the VHF synthesizer is therefore only 1.25 kHz. The integrated PLL circuits used in loop 1 and 2 do not include the prescaler. Therefore, external prescalers with a division ratio of 21/22 are used. The loop filters are of same type as the one used in the L-band synthesizer. The VCO’s are a Colpitts-Clapp type, built up with BJT’s . Before the amplified VCO signals enter the loop mixer, they are low-pass filtered to attenuate the harmonic contents. Loop mixing takes place in a passive double balanced diode mixer, and at the output the mixer, a low-pass filter removes the sum frequency. For initialization and selection of frequencies, the PLL circuits need three signals each: clock, data and strobe. The strobe signal is used for chip selection and therefore three separate wires are used. The clock and data signals are the same for the three PLL’s, the strobe signals determining which one is loaded with data. The strobe, data and clock signals are generated from the TSP board. Each of the three PLL’s has a built in lock detector which indicates when a VCO is unlocked. These signals are combined in a lock indicator circuit which indicates if one or more VCO’s are unlocked. The lock condition is signalled to the TSP board, which sends this information to the transceiver unit. The lock indicator is also connected to a led placed on the synthesizer board, which is lit when a VCO is unlocked. The supply voltages (+18V, +8V, -15.5V) from the SMPS are converted to +15V, +5V and -1.25V by standard voltage regulators but the more critical supply voltages to VCO’s and phase detectors are made by discrete components to lower the noise level.

Inmarsat B PAGE 3-10 9901 3.1.10 SYNTHESIZER FOR UP/DOWN CONVERTER The UP and DOWN converter synthesizers are two separate units but placed on the same printed circuit board. UP converter synthesizer The two local oscillator signals used in the UP converter are generated on this synthesizer module. The first local oscillator which is used to mix the transmitter frequency to first IF is named VHF synthesizer and the other is named L-band synthesizer. The frequency coverage of the two synthesizers are listed below: L-band synthesizer: 1776.915 - 1810.620 MHz in steps of 315 kHz VHF synthesizer: 213.0025 - 213.3150 MHz in steps of 2.5 kHz A block diagram of the UP converter synthesizer is shown in fig. 3.10. LOOP 1 PD :32 VCO :N :64/65 :A PD :63 VCO :N :A :20/21 :A :N :20/21 :64 PD VCO VHF L Band Lock det. LOOP 2 10.08 MHz from Triplexer To TSP from PLL Lock Signals 35534 Fig. 3.10.

Inmarsat B PAGE 3-11 9901 L-band synthesizer The L-band oscillator is based on a voltage controlled oscillator (VCO) with good close in phase noise properties. Frequency stability is obtained using a PLL circuit, the VCO locked to the highly stable reference frequency supplied from the triplexer board. The integrated PLL circuit contains phase detector, divider for reference frequency, divider with modulus two architecture and built in L-band prescaler with a division ratio of 64/65. The 10.08 MHz reference frequency is divided by 32 in the reference divider to obtain a frequency resolution of 315 kHz. The loop filter is an active low-pass filter built up around a low noise operational amplifier. The output signal from the VCO is amplified in two integrated L-band amplifiers (MMIC). The purpose of the amplifiers is not only to obtain the required signal level but also to isolate the frequency determining components in the VCO from the rest of the circuits. VHF synthesizer The VHF synthesizer is also based on PLL technology but because of the high frequency resolution of 2.5 kHz and demands for low phase noise, a dual loop synthesizer is used. The two loops are built up as conventional synthesizers with the exception that loop 1 contains a mixer. The reference divider in loop 1 is 63 giving a frequency resolution of 160 kHz and for loop 2 it is 64, giving a frequency resolution of 157.5 kHz. When the divider in the feed back loop of loop 1 is incremented by 1, the output frequency of the VHF synthesizer is increased by 160 kHz. If at the same time, the divider in the feed back loop of loop 2 is reduced by one, the output frequency of the VHF synthesizer is decreased by 157.5 kHz. The resulting change of frequency at the output of the VHF synthesizer is therefore only 2.5 kHz. The integrated PLL circuits used in loop 1 and 2 do not include the prescaler. Therefore, external prescalers with a division ratio of 21/22 are used. The loop filters are of same type as the one used in the L-band synthesizer. The VCO’s are a Colpitts-Clapp type, built up with BJT’s . Before the amplified VCO signals enter the loop mixer, they are low-pass filtered to attenuate the harmonic contents. Loop mixing takes place in a passive double balanced diode mixer, and at the mixer output, a low-pass filter removes the sum frequency. For initialisation and selection of frequencies, the PLL circuits need three signals each: clock, data and strobe. The strobe signal is used for chip selection, and therefore three separate wires are used. The clock and data signals are the same for the three PLL’s, the strobe signals determining which one is loaded with data. The strobe, data and clock signals are generated from the TSP board. Each of the three PLL’s has a built-in lock detector indicating when a VCO is unlocked. These signals are combined in a lock indicator circuit indicating if one or more VCO’s are unlocked. The lock condition is signalled to the TSP board, which sends this information to the transceiver unit. The lock indicator is also connected to a led, placed on the synthesizer board, which is lit when a VCO is unlocked. The supply voltages ( +18V, +8V, -15.5V) from the SMPS are converted to +15V, +5V and -1.25V by standard voltage regulators, but the more critical supply voltages to VCO’s and phase detectors are made by discrete components to lower the noise level. DOWN converter synthesizer The two local oscillator signals used in the DOWN converter are generated on this synthesizer module. The first local oscillator which is used to mix the receiver frequency to first IF is called L-band synthesizer and the other is called VHF synthesizer. The frequency coverage of the two synthesizers is listed below: L-band synthesizer: 1345.680 - 1379.385 MHz in steps of 315 kHz VHF synthesizer: 200.7200 - 201.0325 MHz in steps of 2.5 kHz A block diagram of the synthesizer module is shown in fig. 3.11.

Inmarsat B PAGE 3-12 9901 LOOP 1 PD :32 VCO :N :64/65 :A PD :63 VCO :N :A :20/21 :A :N :20/21 :64 PD VCO VHF L Band Lock det. LOOP 2 10.08 MHz from Triplexer To TSP from PLL Lock Signals 35534 Fig. 3.11. L-band synthesizer The L-band oscillator is based on a voltage controlled oscillator (VCO) with good close in phase noise properties. Frequency stability is obtained using a PLL circuit, the VCO locked to the highly stable reference frequency supplied from the triplexer board. The integrated PLL circuit contains phase detector, divider for reference frequency, divider with modulus two architecture and built in L-band prescaler with a division ratio of 64/65. The 10.08 MHz reference frequency is divided by 32 in the reference divider to obtain a frequency resolution of 315 kHz. The loop filter is an active low-pass filter built up around a low noise operational amplifier. The output signal from the VCO is amplified in two integrated L-band amplifiers (MMIC). The purpose of the amplifiers is not only to obtain the required signal level but also to isolate the frequency determining components in the VCO from the rest of the circuits. VHF synthesizer The VHF synthesizer is also based on PLL technology but because of the high frequency resolution of 2.5 kHz and demands for low phase noise, a dual loop synthesizer is used. The two loops are built up as conventional synthesizers with the exception that loop 1 contains a mixer. The reference divider in loop 1 is 63, giving a frequency resolution of 160 kHz, and for loop 2 it is 64, giving a frequency resolution of 157.5 kHz. When the divider in the feed back loop of loop 1 is incremented by 1, the output frequency of the VHF synthesizer is increased by 160 kHz. If at the same time, the divider in the feed back loop of loop 2 is reduced by one, the output frequency of the VHF synthesizer is decreased by 157.5 kHz. The resulting change of frequency at the output of the VHF synthesizer is therefore only 2.5 kHz.

Inmarsat B The integrated PLL circuits used in loop 1 and 2 do not include the prescaler. Therefore, external prescalers with a division ratio of 21/22 are used. The loop filters are of same type as the one used in the L-band synthesizer. The VCO’s are a Colpitts-Clapp type, built up with BJT’s . Before the amplified VCO signals enter the loop mixer, they are low-pass filtered to attenuate the harmonic contents. Loop mixing takes place in a passive double balanced diode mixer, and at the output the mixer, a low-pass filter removes the sum frequency. For initialisation and selection of frequencies, the PLL circuits need three signals each: clock, data and strobe. The strobe signal is used for chip selection and therefore three separate wires are used. The clock and data signals are the same for the three PLL’s, the strobe signals determining which one is loaded with data. The strobe, data and clock signals are generated from the TSP board. Each of the three PLL’s has a built-in lock detector indicating when a VCO is unlocked. These signals are combined in a lock indicator circuit indicating if one or more VCO’s are unlocked. The lock condition is signalled to the TSP board, which sends this information to the transceiver unit. The lock indicator is also connected to a led, placed on the synthesizer board, which is lit when a VCO is unlocked. The supply voltages ( +18V, +8V, -15.5V) from the SMPS are converted to +15V, +5V and -1.25V are generated by standard voltage regulators, but the more critical supply voltages to VCO’s and phase detectors are made by discrete components to lower the noise level. 3.1.11 SWITCH MODE POWER SUPPLY The 40V DC supplied from the transceiver unit is converted to different voltage levels needed to supply the modules and motors. This is done in the switch mode power supply. Actually the power supply consists of two power units based on switch mode technology. The two switch circuits in power units 1 and 2 are synchronised to minimise spurious and avoid beat tones, which can be a problem when a module is supplied from both power units. A block diagram is shown in fig. 3.12. Power Unit 1 Circuit Synch. Power Unit 2 Converter D/A Timer Clock Data Strobe DMB from HPA DMB from TSP +28VR +18V +24V +28V -16V +8V +12V Connection Board 40V DC from Register Shift 35525 Fig. 3.12. The first power unit generates all fixed voltages and the second power unit generates a variable voltage between 4 and 28V DC to control the transmitter power of the HPA. The level of the variable voltage is controlled from a microcontroller placed in the HPA. The microcontroller is connected to a digital to analogue converter through a serial connection. The serial data stream is organised in 8 bit groups clocked into a shift register and thus converted to 8 bits in parallel. The seven most significant bits are used as input for the D/A converter and select voltage level. The least significant bit is used to switch off the power of the HPA. This feature is used when the HPA is transmitting in burst mode. PAGE 3-13 9901

Inmarsat B To avoid uncontrolled transmission during a fail condition, a signal called dead man’s button (DMB) is used to control the 28V adjustable voltage. Two modules generate DMB signals, i.e. HPA and TSP. DMB signals are square wave voltages with frequencies of 500 Hz and 3 kHz respectively. The signals are used to refresh a timer and if one is missing, the adjustable voltage, and thus the transmitter signal, are shut down. The HPA stops generating the dead man’s button signal in case of a fail condition like power too high, burst too long or overheated module. If for some reason, data communication between ADE and BDE breaks down, the TSP stops generating the DMB signal. The different kind of voltages and what they are used for are listed below. +28VR: 28V adjustable for HPA power control. Can be switched off from microcontroller (CPU) located in the HPA. +28V: Fixed 28V supply for HPA. Can be switched off from CPU. +24V: Fixed 24V supply for motors. +18V: Fixed 18V supply for small signal electronics. +12V: Fixed 12V supply for HPA. Can be switched off from CPU. +8V: Fixed 8V supply for digital electronics. -16V: Fixed -16V supply for small signal electronics. 3.1.12 TSP The TSP board is the central control unit in the ADE. Its main task is to control the antenna pointing stabilisation, satellite search and satellite tracking. In addition it takes care of control data communication with the BDE, synthesizer setup and locking surveillance, and exchange of control and status information with the HPA controller. A block diagram is shown in fig. 3.13. Memory block V10 V9 V8 CPU Connectors D/A converter Output section Registers +2.5V, -2.5V +14V, +5V, -5V, -11V Power supply Measurement section Buffer, filter 35967 Fig. 3.13. The program code for the TSP is placed in two flash proms mounted in 32 pin plcc cases in one of the corners of the board. The code is divided in an even and an odd part. The prom closest to the MC68HC16 CPU and the centre of the board holds the even code part, the other holds the odd part. Exchanging proms If replacement of the proms is needed, note that the software can be exchanged as physical PROM's or as ADE upload (see section 6.1.2) 1) The main power must be off during the operation. 2) To distinguish between even/odd prom, see chapter 5. 3) Align the notched corner of the plcc’s with the cut corner of the sockets (alignment mark). 4) Before inserting the new proms in the socket be sure that no pins of the prom or the socket have been bent or somehow misaligned in any way. PAGE 3-14 9936

Inmarsat B The LEDs The TSP board is equipped with 3 LEDs (smd types): A pair consisting of a red (V10) and a green (V9) placed between the CPU and the SRAM and a red LED (V8) placed almost at the centre of the board. V8, red LED, reset source indicator This LED should normally always be on after power on/off reset and stay on as long as the power is turned on. It must only be off after a soft reset (through service interface) or after a software update by upload (also ending with a soft reset of the TSP). If this LED is turned off in any other situation than described above a failure has occurred on the TSP board. Check to see that the flash proms are correctly aligned and that no pins have been bent or damaged. If this does not help, the proms or the complete TSP board must be replaced. V9, green LED, test/debug LED This LED is normally used for factory test and debug purposes. During upload of a new program to the TSP, V9 will flash quickly each time a block of the new program code has been received and stored in the TSP upload buffer. If V9 does not flash during upload, no program data is received from the BDE, and it is most likely that the upload does not work correctly. Check the interface between the service PC and the BDE, and check if any error messages from the BDE are shown on the service interface PC. V10, red LED, alive indicator This LED always flashes with a total period of 1 second. The flashing will pause a few seconds after reset and then start flashing. 3.1.13 TILT SENSOR The main component of this module is a dual axis tilt sensor, which is a vertical sensing electrolytic potentiometer providing a linear voltage output as the unit is tilted around the horizontal axis. The unit is a hermetically sealed glass enclosure with five internal electrodes. One common electrode is placed at the vertical centre line, and two pairs of electrodes (called x and y direction) are placed on orthogonal axes. Because the sensor contains an electrolyte, the drive signal has to be an AC voltage. A block diagram of the module is shown in fig. 3.14. S & H S & H S & H S & H Network Sampling Network Combiner Network Sampling Sensor multivibrator Astable X Y 35969 Fig. 3.14. The AC voltages for the four tilt sensor inputs are derived from an astable multivibrator and two frequency divider circuits built up with D type flip flops. The AC voltages for the two x inputs are out of phase. This is also the case with the y inputs. The common output from the tilt sensor is connected to four sample and hold amplifiers. A combinatorial network generates four sample and hold signals, one at a time, to the amplifiers. A subtraction circuit built up with operational amplifiers combines the two x signals to a single signal which then is offset in amplitude to generate zero output when the tilt angle is zero. The resulting y signal is made with a circuit equal to the one used to generate the x signal. PAGE 3-15 9849

Inmarsat B 3.2 BELOW DECK EQUIPMENT 3.2.1 SPS BOARD The SPS board consists of baseband for IF converters to both transmitter and receiver signal paths, data receiver and transmitter equal to those placed on the triplexer board, the system reference oscillator and a digital signal processor for carrier and clock synchronisation. A block diagram of the SPS board is shown in fig. 3.2.1. TX-Modulator TX-LO SC-LPF SC-LPF LO TX-SC Doubler Freq. OCXO De-Modulator DSP RX-LO LO RX-SC SC-LPF SC-LPF A/D A/D 21.4 MHz Quad- Plexer Shift Register 24 bit 99 MHz TX Data RX Data 87 MHz 87 MHz OSC Q-Data to modem I-Data to modem TX-I from modem TX-Q from modem 40.32 MHz 20.16 MHz 12 12 4 4 35532 Fig. 3.2.1. Transmitter path The TX baseband signals (TX-I, TX-Q) generated at the modem board are filtered in a pair of switch capacitor filters. The cut off frequency of those filters can be changed by changing the filter clock frequency. The clock frequency is generated by the TX-SC synthesizer and depends on the selected service type. The filtered signals are mixed with a 62.9 MHz local oscillator signal (TX-LO) in a quadrature mixer to form the final TX IF signal. The 62.9 MHz transmitter local oscillator is built up around a traditional PLL integrated circuit. Receiver path The 21.4 MHz IF signal from the antenna is taken out from the quadplexer and unwanted signals are attenuated in the low-pass filter. The IF signal is down converted to baseband in a quadrature demodulator. The demodulator as shown in fig 3.2.1 is built up around two passive double balanced diode mixers. The RF input for the mixers is the 21.4 MHz IF signal split equally in amplitude and with the same phase. The local oscillator signal for the two mixers is of equal amplitude and frequency but 90° out of phase. This phase shift is made by shifting one of the oscillator signals +45° and the other -45°. The two PAGE 3-16 9936

Inmarsat B I and Q baseband signals taken out of the IF ports of the mixers are amplified by operational amplifiers before they are filtered in low-pass switch capacitor filters. Those filters are of the same type as those used in the transmitter part. The cut off frequency of the filters is selected by the frequency of the RX-SC synthesized oscillator. The output signals of the switch capacitor filters are further amplified before they are sampled in two 12 bit analogue to digital converters. The data format out of these A/D converters is a 12- bit parallel format converted to a serial bit stream in a 24 bit shift register. This serial bit stream representing the sampled I and Q signals is clocked into the digital signal processor. Data receiver From the quadplexer, the data signal transmitted from the triplexer at the antenna unit is filtered out in a 99 MHz bandpass filter. The data receiver is built up around the same FM integrated subsystem where an 87 MHz crystal oscillator is used to down convert the 99 MHz data signal to a 12 MHz IF before the data bit is recovered in the FM detector. The 4800 baud data stream is transferred to the CSP/VDP board. Data transmitter The data transmitter is built up as an FSK modulator equal to the one placed on the triplexer board. The data stream which is received from the CSP/VDP board is modulated into a carrier of 87 MHz with a frequency shift of ± 150 kHz. A high-pass filter with a cut off frequency of 83 MHz increases the isolation between the 62.9 MHz transmitter signal and the vector modulator in the data transmitter to lower intermodulation products. Finally the signal level from the data transmitter is amplified before it enters the quadplexer. Reference oscillator Due to the rigorous frequency accuracy requirement over a relatively wide temperature range, an oven controlled crystal oscillator of 20.16 MHz is used to derive all critical reference frequencies. A frequency doubler generates a 40.32 MHz signal to the ADE. PAGE 3-17 9936

Inmarsat B 3.2.2 MODEM BOARD The modem is the module which takes care of the coding/decoding of data/baseband signals. Depending on which service types the transceiver unit covers, different modem configurations can be found in it. A combined modem (629347) covers all service types. It handles LSD as well as HSD, and TX as well as RX. The modem has two main functions: - A modulator converts the digital transmission data to an analogue baseband signal (formed by an I and a Q channel). - A decoder converts the received digital baseband (also formed by an I and a Q channel, each consisting of 4 parallel bits) to received data. The modem employs Forward Error Correction (FEC) and scrambling (randomisation) techniques to achieve the error free performance in accordance with Inmarsat requirements. The block diagram shown in fig. 3.2.2 is for all modem variants. detection & Sync. word ambiguity resolution decoder & descrambler Viterbi/ sequential Ser. interface with VDP Control interface with VDP with VDP Ser. interface filters shaping Output convolutional coder Scrambler DAC DAC Rx Status/control Data buffer Bidir Isymb. Qsymb. +3.3V +5V Power supply Tx Tx Tx 35968 Fig. 3.2.2 A digital core performs all control, processing and communication as well as the outputting of data to the A/D converters for the analogue output circuitry. The buffer, power and output circuitry is peripheral to the digital core, which is formed by a single combi ASIC. The following is a description of the interface to and from the PAX board: X1: The modem is controlled through this connector via the TU bus (parallel interface) from the CSP/ VDP board. Certain data (telex and SUs) is provided to the modem through the TU bus. All communication to and from the CSP runs in this connector. X3: Serial synchronous interface to CSP/VDP board for TX and RX data. Also the reference clock and some status signals pass through this connector. X5 : Interfaces RX and TX baseband signals to the SPS board and provides power input (+7.5V and -15V). PAGE 3-18 9936

Inmarsat B 3.2.3 CSP/VDP BOARD The board (630953) is called the CSP/VDP module and consists basically of two functionally separate parts. The CSP (control and signalling processor) is the main system processor, which takes care of the satellite protocol, man/machine and external equipment interfaces. A block diagram of the module is shown in fig. 3.2.3. MUX PCM MUX Clock Gen. VDP ACIA CSP CAN TU bus Pax Board From/to Scanbus Scanbus ADE Data NMEA PC/Printer Tubus Alarm 35965A Fig 3.2.3 The VDP (voice and data processor) is a digital signal processor which handles voice encoding and decoding, and acts as the interface between the baseband modem and the PAX module for the fax and data services. The software for the CSP and VDP is contained in the same set of EPROMs and transferred by the CSP to the VDP when powering on. The CSP controls the signal routing around the VDP and has the following interface paths: X1: Contains an 8-bit parallel data interface, is used to control all other boards in the transceiver. X2: Contains 5 asynchronous serial data interfaces for the telex terminal, telex printer, service terminal, NMEA position and NMEA gyro. Inputs from the external distress buttons are also connected through X2. X3: Contains the asynchronous serial data interface to the antenna, which is modulated into a carrier on the SPS board. X4: Contains the scanbus which is the interface to the control units and future expansions. The CSP is involved in the digital part through a data network called CAN (controller area network). - The VDP is connected directly to the CSP data bus. The VDP has the following interface paths: X3: Contains a synchronous serial data interface to the baseband modem. X4: Contains the audio part of the scanbus. X7: Contains a synchronous data interface to the PAX module, used for the fax and data services. PAGE 3-19 9936

Inmarsat B 3.2.4 PAX BOARD The PAX board (631593) is an advanced interface for data, facsimile and phones. The board is controlled from the CSP/VDP board through the TU bus. The central processor on the pax board, AM186EM-40, is an embedded version of the 186 processor, which is able to run on 186 code. The chosen processor is faster than the 186, and has more built-in functions. A block diagram is shown in fig. 3.2.4. MUX SLIC SLIC Connector Phone 1 Phone 2 ACIA MUX FAX Control SCIA To VDP To VDP PC/Printer 35966 Fig. 3.2.4. The data part is fully hayes compatible, and capable of running high speed 64 kbps full duplex data as well as 9600 kbps (ARQ/NARQ) full duplex data. Connection to the PAX board is handled by a high speed ACIA, as in most modern PCs or modems. The facsimile connection can be made through either of the two phone connectors, with a maximum transmission speed of 9600 kbps. The handling of fax calls, the T.30 protocol used in all fax communi- cation, and the DTMF tone detection are done by an integrated circuit. Either of the two phone connectors can also be used for ordinary analogue telephones or PABX connections. The system detects during startup if a PABX is connected, and automatically configures the system for this. The phone system is fitted with an advanced voice guide which can guide the user through the sequence of changing earth station and network. Two separate SLICs (subscriber line interface circuits) handle the two phone connectors. On the edge of the PAX board, 5 connectors are used to interface to the other boards in the transceiver unit. A short description of each connector is given below: X1: TU bus connection to the CSP/VDP board. All communication to and from the CSP runs in this connector. X2: Serial communication supply and +40V DC for the SLIC circuits. X5: Analogue voice connection to CSP/VDP board, supply voltages and PABX interrupt. X6: Connections to the two phone connectors, data and optional PC connections. X7: Synchronous interface to and from the CSP/VDP board. Fax and data communication. PAGE 3-20 9936

Inmarsat B 3.2.5 SMI BOARD The switch mode power supply and interconnection board consists basically of two independent units. The interconnection takes care of the interface between SUB-D connectors at the rear panel of the transceiver unit and the modules inside it. A block diagram is shown in fig. 3.2.5. Power Ant. Scanbus NMEA Data Pc/Printer Alarm Phone 2 Phone 1 X1 X2 X3 X4 Ribbon cable connectors to transceiver modules Rear panel connectors Connection circuit Filter 40V DC Conv. 40V DC Conv. 40V DC Conv. Multi Conv. Control circuit DC/DC Conv. -12V +12V +40V -15V +15V +24V +8V 35970 Fig. 3.2.5. The supply voltage delivered from the ship to the transceiver unit is 24V DC nominal but can range from 20 to 40V DC. From the input voltage, the switch mode power supply generates the following voltages: +40V DC - 7A +12V DC - 0.1A -12V DC - 0.1A +15V DC - 0.25A -15V DC - 0.15A +7.5V DC - 2.6A +24V DC - 0.4A The switch mode power supply is built up as four converter modules, placed on a main board containing all the DC control circuits. Three of the converter modules generate 40V DC and are coupled in parallel, i.e. only one 40V DC is available. The fourth converter is a multi converter generating all internally used voltages in the transceiver unit. The 40V DC is used as main voltage for the antenna unit, as input for the multiconverter and finally as input for a special DC/DC converter placed on the main board generating ±12V DC for RS 232 terminals connected to the transceiver unit. All the converters are placed inside a metal screen to prevent emission of noise. A heat sink is placed on top of the converters. Therefore, when the transceiver unit is working, the blower inside the transceiver unit must always be connected. 40V DC converter module This module is a push-pull converter, basically controlled by a current mode controller, which is controlled and synchronised by the control circuit on the main board. Multiconverter module This module contains two converters. The first one is a step DOWN converter converting the 40V DC down to 7.5V DC which supplies the 5V regulators placed on the different boards inside the transceiver unit. The second converter is a fly back version, which creates ±15V DC for the transceiver modules and +24V DC mainly used to supply the control unit and handset. The multiconverter is also synchronised with the 40V DC converters. PAGE 3-21 9936

Inmarsat B 3.2.6 HANDSET The handset is connected to the transceiver unit through the Scanbus which contains both analogue and digital signals. The analogue signals are microphone signal from handset and loudspeaker signal to the handset. Both signals are balanced. PAGE 3-22 9936

4-1 4.2 SD4360 DISTRESS BUTTON 4-1 4.3 H4394/95 VERITAS CONNECTION BOX 4-1 4.4 H4396 T-CONNECTION BOX 4-2 9849 Inmarsat B

units and units used for installation. 4.1 SC4350 CONTROL UNIT The Control Unit SC4350 is a desk/bulkhead mounted keyboard/display unit, using a handset without display/keyboard. Normal user interface, as well as system setup, can be carried out from the unit. All operations are performed from the unit’s front panel. In all essentials, the functions of the Control Unit SC4350 are the same as those of the Handset SC4345. The Control Unit SC4350 can be used instead of the Handset SC4345, or it can be used as an additional Control Unit, as a total of up to 5 Handsets/Control Units can be connected to the system. To BDE Circuits Analogue Keyboard Transceiver Micro- processor Circuits +24V Speaker Display Handset 36823 The Control Unit SC4350 is connected to the BDE transceiver via the so-called “Scanbus”, which contains digital communications (Canbus), audio-frequency signals (2 “twisted pairs”, balanced lines, one for each direction, microphone to BDE transceiver, and BDE transceiver to earpiece/loudspeaker), and power- supply wires. Connection may be directly to the BDE transceiver’s “Scanbus” connector, or via a “Veritas connection box”. If more than one Control Unit are to be connected to the system, H4396 connection boxes are used. All connected Control Units are 100% electrically parallelled. The unit is not “intelligent”. When for example a key is pressed, information about which key was pressed, is passed to the BDE transceiver, which interprets the key-press code and returns new display information, signal path setup information, sounder setup, or whatever may be relevant in the given situation. The SC4350 then executes these commands. Please note, in case of service or repair: The unit can do virtually nothing if not connected to a BDE transceiver. 4.2 SD4360 DISTRESS BUTTON The distress button can be used in connection with a push button telephone or a telex terminal. The function is the same as the one placed in the handset hook. A block diagram is shown in fig. 4.3. Key Distress Timer To/from Indicator Converter Level Regulator Voltage Alarm Connector 35533 Fig. 4.3. PAGE 4-1 9936 Inmarsat B

The distress key activates a timer circuit which generates a 9 Hz square wave voltage until the key is released. The square wave voltage is modified in the level converter to interface to the open collector circuit in the alarm connector. An indicator circuit consisting of light and a 3 kHz tone is activated from the alarm connector during a distress alert. A voltage regulator generates the needed 12V DC to the timer and indicators. 4.3 H4394/95 VERITAS CONNECTION BOX A Veritas connection box is the interface between the SUB-D connectors at the transceiver unit rear panel and the ship installations. A diagram and component placements are shown below. All SUB-D connectors at the transceiver unit are connected to their respective SUB-D connectors inside the Veritas connection box. In the box, connections between SUB-D and the wire terminal blocks to the ships installation cables are made. Two relays inside the Veritas connection box can be used to activate externally mounted indicators on the ship like alarms, horns, lamps etc. The relays, if used, can be connected to the alarm connector and indicate service announcements or distress transmitted. The functions of the relays are set up during installation. A gyro repeater is also included and can be used if the NMEA signal from the ship gyro compass is not available.

Component location T-Connection box Diagram T-Connection box

SOFTWARE LOCATION 5-1 5.1 ANTENNA UNIT 5-1 5.1.1 MODULE AND SENSOR LOCATION 5-1 5.1.2 MECHANICAL DISASSEMBLING 5-2 5.1.2.1 CHANGING AZIMUTH TIMING BELT 5-2 5.1.2.2 CHANGING ELEVATION TIMING BELT 5-2 5.1.2.3 CHANGING CROSS ELEVATION TIMING BELT 5-2 5.1.2.4 CHANGING HORIZONTAL AXIS TIMING BELT 5-3 5.1.3 CONNECTORS AND SOFTWARE LOCATION 5-4 5.1.3.1 UP/DOWN CONVERTER UNIT 5-4 5.1.3.2 TRACKING RECEIVER UNIT 5-5 5.1.3.3 HPA 5-6 5.1.3.4 DIPLEXER/LNA 5-7 5.1.3.5 TSP 5-7 5.1.3.6 TRIPLEXER 5-10 5.1.3.7 SMPS 5-11 5.1.3.8 STEP MOTOR DRIVER 5-13 5.1.3.10 DC MOTOR DRIVER 5-14 5.1.3.11 TILT SENSOR 5-15 5.1.3.12 FLUXGATE COMPASS 5-15 5.1.3.13 ZERO-MARK DETECTOR 5-16 5.1.3.14 INTERCONNECTION BOARD 5-16 5.2 TRANSCEIVER UNIT 5-17 5.2.1 MODULE LOCATION 5-17 9849 Inmarsat B

5-18 5.2.2.1 SPS BOARD 5-22 5.2.2.2 CSP/VDP BOARD 5-22 5.2.2.3 PAX BOARD 5-23 5.2.2.4 SMI 5-23 5.2.2.5 LSD, HSD FPGA AND COMBI MODEM 5-24 5.3 HANDSET 5-25 5.3.1 SOFTWARE LOCATION 5-25 5.4 CONTROL UNIT 5-25 5.4.1 SOFTWARE LOCATION 5-25

5.1 ANTENNA UNIT 5.1.1 MODULE AND SENSOR LOCATION 1 6 2 7 3 4 8 5 Fig. 5.1 1. Tracking receiver unit part no. 729840 2. HPA part no. 729430 3. Diplexer/LNA part no. 730630 4. DC motor controller for cross elevation axis part no. 634686 5. Step motor driver for horizontal axis part no. 629362 6. Step motor driver for elevation axis motor part no. 629362 7. SMPS part no. 629364 8. Rate sensor for cross elevation axis part no. 41.603 9. ADE fuse part no. 45.510 Fig. 5.2 1. Up/down converter unit part no. 730650 2. Connection board part no. 629349 3. Triplexer part no. 629358 4. TSP part no. 630814 5. Step motor driver for azimuth axis part no. 629362 Fig. 5.3 1. ADE on/off switch 2. Tilt sensor part no. 629366 3. Rate sensor for elevation axis part no. 41.603 4. Rate sensor for azimuth axis part no. 41.603 1 5 1 2 3 4 2 3 4 9 Inmarsat B

Scansat-B PAGE 5-2 9936 1 2 5.1.2 MECHANICAL DISASSEMBLING 5.1.2.1 CHANGING AZIMUTH TIMING BELT Fig. 5.4 1. Loosen the four screws holding the motor part no. 87.434 2. Remove the 3 mm screw holding the connection print part no. 86.962 3. Remove three 2.5 mm screws, and remove the connection print part no. 86.004 Change the timing belt. 3 5.1.2.2 CHANGING ELEVATION TIMING BELT Fig. 5.5 1. Remove the plug from the motor driver pcb 2. Loosen the four screws holding the motor part no. 87.443 3. Remove one 4 mm screw part no. 87.285 4. Remove twelve 3 mm screws part no. 86.963 5. Remove six 4 mm screws part no. 87.285 6. Remove three 8 mm bolts part no. 87.902 7. Remove the side panel part no. 230623 Change the timing belt. ** * ** * * * * * * * 1 4 * 3 # # # # # # 5 # 6 7 § § § § 2 § 5.1.2.3 CHANGING CROSS ELEVATION TIMING BELT Fig. 5.6 1. Loosen the four screws holding the motor Lower screws part no. 87.452 Upper screws part no. 87.453 2. Remove two 5 mm screws part no. 87.453 and the timing belt lock part no. 63.612 Change the timing belt. 2 1 part no. 48.853 part no. 736888 part no. 736889 part no. 736889 part no. 48.852 part no. 530663 part no. 736890

Inmarsat B PAGE 5-3 9936 5.1.2.4 CHANGING HORIZONTAL AXIS TIMING BELT Fig. 5.7 1. Loosen the four screws holding the motor part no. 86.962 2. Loosen one 5 mm bolt, part no. 87.421 and remove the horizontal axis Change the timing belt. 2 1 part no. 48.855 part no. 736891

Inmarsat B PAGE 5-4 9905 5.1.3 CONNECTORS AND SOFTWARE LOCATION 5.1.3.1 UP/DOWN CONVERTER UNIT PART no.: 730650 Connections: Connector no.: X1, X2, X3, X4, X5 Connector type: SMA, Coax Connector no. Connection name To/from X1 62.9 MHz input to up converter Triplexer X2 L-band output from up converter HPA X3 10.08 MHz reference to synthesiser Triplexer X4 21.4 MHz IF from down converter Triplexer X5 L-band input to down converter Diplexer/LNA unit Connector no.: X6 Connector type: Molex, 2 x 10 pins Pin no. Connection name Colour To/from 1 No connection 2 No connection 3 -15.5V DC Brown SMPS 4 Ground Black 5 +18V DC Orange SMPS 6 +8V DC Red SMPS 7 STB2 LO2 D White TSP 8 STB LO1 D Violet TSP 9 LOCK DET 1 Violet TSP 10 STB1 LO2 D Grey TSP 11 STB LO2 U Green TSP 12 LOCK DET 2 Blue TSP 13 STB1 LO1 U Green TSP 14 STB2 LO1 U Blue TSP 15 STBD Grey TSP 16 RXL White TSP 17 GROUND Black 18 STBU Violet TSP 19 DATA Green TSP 20 CLOCK Blue TSP X3X6 X4 X5 X1 X2

Inmarsat B 9905 PAGE 5-5 5.1.3.2 TRACKING RECEIVER UNIT PART no.: 729840 Connections: Connector no.: X1, X3 Connector type: SMA, Coax Connector no. Connection name To/from X1 L-band input to tracking receiver Diplexer/LNA unit X3 10.08 MHz reference to synthesiser Triplexer Connector no.: X2 Connector type: Molex, 14 pins Pin no. Connection name Colour To/from 1 No connection 2 No connection 3 -15.5V DC Brown SMPS 4 Ground Black 5 +18V DC Orange SMPS 6 +8V DC Red SMPS 7 Ground Black 8 STS Green TSP 9 STB2 LO2 T White TSP 10 STB LO1 T Blue TSP 11 CLOCK Violet TSP 12 STB1 LO2 T Grey TSP 13 LOCK DET Green TSP 14 DATA Blue TSP X3 X2 X1

Inmarsat B 5.1.3.3 HPA PART no.: 729430 Connections: Connector no.: X1, X2 Connector type: SMA, Coax Connector no. Connection name To/from X1 Output from HPA Diplexer X2 Input to HPA Up converter Connector no.: X3 Connector type: Molex, 2 X 10 pins Pin no. Connection name Colour To/from 1 +28RV DC Yellow SMPS 2 +28RV DC Yellow SMPS 3 +28RVDC Yellow SMPS 4 Ground Black SMPS 5 +28V Orange SMPS 6 Ground Black SMPS 7 +12V Orange SMPS 8 Ground Black SMPS 9 +7.5V Red SMPS 10 Test TSP 11 DMB 2 Blue SMPS 12 STB PC Green TSP 13 CLK White TSP 14 DATA Grey TSP 15 Ground Black SMPS 16 DATA OUT White TSP 17 DATA IN Grey TSP 18 CLK Violet TSP 19 SS Blue TSP 20 PORT Green TSP PAGE 5-6 9905 X1 X2 X3

Inmarsat B 5.1.3.4 DIPLEXER/LNA PART no.: 730630 Connections: Connector no.: X1, X2, X3, X4 Connector type: SMA, Coax Connector no. Connection name To/from X1 LNA output Down converter X2 LNA output Tracking receiver X3 Diplexer input/output Antenna X4 Diplexer input, Tx HPA 5.1.3.5 TSP PART no.: 630814 PAGE 5-7 9849 X3 X4 X1 X2

Inmarsat B Software: Component no. Description Spare part no. D15 Tracking & stabilisation 732514 D16 Tracking & stabilisation 732515 Connections: Connector no.: X19 Connector type: 3M, 2 x 5 pins Pin no. Connection name Colour To/from 1 +18V Grey, ribbon cable SMPS 2 +8V Grey, ribbon cable SMPS 3 +8V Grey, ribbon cable SMPS 4 -15.5V Grey, ribbon cable SMPS 5 Ground Grey, ribbon cable SMPS 6 DMB_1 Grey, ribbon cable SMPS 7 RXD_FROM_BDE Grey, ribbon cable Triplexer 8 TXD_TO_BDE Grey, ribbon cable Triplexer 9 No connection Grey, ribbon cable 10 No connection Grey, ribbon cable Connector no.: X20 Connector type: MOLEX, 2 x 12 pins Pin no. Connection name Colour To/from 1 LOCKDET_T Green Tracking receiver unit 2 SYNTH_DATA Blue Tracking receiver unit 3 SYNTH_SCLK Violet Tracking receiver unit 4 STB1LO2T Grey Tracking receiver unit 5 STB2LO2T White Tracking receiver unit 6 STBLO1T Blue Tracking receiver unit 7 Ground Black Tracking receiver unit 8 Tracklevel Green Tracking receiver unit 9 SYNTH_DATA Green Up/Down converter unit 10 SYNTH_SCLK Blue Up/Down converter unit 11 Ground Black Up/Down converter unit 12 STBU violet Up/Down converter unit 13 STBD Grey Up/Down converter unit 14 No connection White Up/Down converter unit 15 STB1LO1U Green Up/Down converter unit 16 STB2LO1U Blue Up/Down converter unit 17 STBLO2U Green Up/Down converter unit 18 LOCK_DET1 Blue Up/Down converter unit 19 LOCKDET_2 Violet Up/Down converter unit 20 STB1LO2D Grey Up/Down converter unit 21 STB2LO2D White Up/Down converter unit 22 STBLO1D Violet Up/Down converter unit 23 No connection 24 No connection PAGE 5-8 9905

Inmarsat B Connector no.: X22 Connector type: MOLEX, 2 x 3 pins Pin no. Connection name Colour To/from 1 HPA_SEL Green HPA 2 HPA_READ_REQ Blue HPA 3 HPA_DATA_CLOCK Violet HPA 4 HPA_DATA_TO_HPA Grey HPA 5 HPA_DATA_FROM_HPA White HPA 6 Ground Black HPA Connector no.: X24 Connector type: MOLEX, 2 x 20 pins Pin no. Connection name Colour To/from 1 El_PHASE_A Green Step motor driver, El 2 Ground Black Step motor driver, El 3 El_PHASE_B Blue Step motor driver, El 4 El_PHASE_C Violet Step motor driver, El 5 No connection 6 El_PHASE_D Grey Step motor driver, El 7 CE_PHASE_A Green Motor driver, CE 8 Ground Black Motor driver, CE 9 CE_PHASE_B Blue Motor driver, CE 10 CE_PHASE_C Violet Motor driver, CE 11 No connection 12 CE_PHASE_D Grey Motor driver, CE 13 No connection 14 No connection 15 CE_RATE White Rate sensor, CE 16 No connection 17 X4_PHASE_A Green Step motor driver, HZ 18 Ground Black Step motor driver, HZ 19 X4_PHASE_B Blue Step motor driver, HZ 20 X4_PHASE_C Violet Step motor driver, HZ 21 No connection 22 X4_PHASE_D Grey Step motor driver, HZ 23 X4_ZERO White Zero mark det. 24 Ground Black Zero mark det. 25 FLXG_Y Violet Fluxgate compass 26 FLXG_X Grey Fluxgate compass 27 Ground Black Fluxgate compass 28 No connection 29 Tilt_X Blue Tilt sensor 30 Tilt_Y Violet Tilt sensor 31 Ground Black Tilt sensor 32 No connection 33 No connection 34 Az_RATE_OFFSET White Motor driver, CE 35 Az_Rate White Rate sensor, Az 36 No connection 37 No connection 38 No connection 39 El_Rate White Rate sensor, El 40 No connection PAGE 5-9 9849

Inmarsat B Connector no.: X27 Connector type: MOLEX, 2 x 5 pins Pin no. Connection name Colour To/from 1 AZ_PHASE_A Green Step motor driver, Az 2 Ground Black Step motor driver, Az 3 AZ_PHASE_B Blue Step motor driver, Az 4 AZ_PHASE_C Violet Step motor driver, Az 5 No connection 6 AZ_PHASE_D Grey Step motor driver, Az 7 AZENC_PHA Green Not used 8 AZENC_PHB Blue Not used 9 Ground Black Not used 10 No connection 5.1.3.6 TRIPLEXER PART no.: 629358 Connections: Connector no.: X2, X3, X4, X5, X6 Connector type: SMB, coax Connector no. Connection name To/from X2 Composite input/output signal Connection board X3 21.4 MHz IF signal Down converter X4 62.9 MHz IF signal Up converter X5 10.08 MHz reference signal Up/down converter X6 10.08 MHz reference signal Tracking receiver PAGE 5-10 9905

Inmarsat B Connector no.: X1 Connector type: 3M, 2 x5 pins Pin no. Connection name Colour To/from 1 +18V DC Grey ribbon cable SMPS/Tsp 2 +8V DC Grey ribbon cable SMPS/Tsp 3 +8V DC Grey ribbon cable SMPS/Tsp 4 No connection Grey ribbon cable SMPS/Tsp 5 Ground Grey ribbon cable SMPS/Tsp 6 No connection Grey ribbon cable SMPS/Tsp 7 Rx data Grey ribbon cable SMPS/Tsp 8 Tx data Grey ribbon cable SMPS/Tsp 9 No connection Grey ribbon cable SMPS/Tsp 10 No connection Grey ribbon cable SMPS/Tsp 5.1.3.7 SMPS PART no.: 629364 P5 P3 P6 P4 P2 P1 29364A50 F1 Fuse: Component no. Description Spare part no. F1 Fuse for 40V conv. 45.510 Connector no.: P1 Connector type: 2 x 2 pins Pin no. Connection name Colour To/from 1 +40V Red Inter connection board 2 Ground Black Inter connection board 3 +40V Red Inter connection board 4 Ground Black Inter connection board PAGE 5-11 9936

Inmarsat B Connector no.: P2 Connector type: 2 x 7 pins Pin no. Connection name Colour To/from 1 +28RV Yellow HPA 2 +28RV Yellow HPA 3 +28RV Yellow HPA 4 Ground Black HPA 5 +28V Orange HPA 6 Ground Black HPA 7 +12V Orange HPA 8 Ground Black HPA 9 +7.5V Red HPA 10 No connection 11 DMB2 Blue HPA 12 STB PC Green HPA 13 CLK White HPA 14 DATA Grey HPA Connector no.: P3 Connector type: 2 x 8 pins Pin no. Connection name Colour To/from 1 +24V Yellow Step motor driver, El 2 Ground Black Step motor driver, El 3 +24V Yellow BLDC motor driver, Ce 4 Ground Black BLDC motor driver, Ce 5 +24V Yellow Step motor driver, Horison. 6 Ground Black Step motor driver, Horison. 7 +18V Not used 8 -15.5V Not used 9 Ground Black Rate sensor, CE 10 +8V Red Zero mark det. 11 Ground Black Zero mark det. 12 +18V Orange Compass 13 +8V Red Compass 14 -15.5V Brown Compass 15 Ground Black Compass 16 No connection Connector no.: P4 Connector type: 2 pins Pin no. Connection name Colour To/from 1 +28V Red Fan 2 Ground Blue Fan PAGE 5-12 9905

Inmarsat B Connector no.: P5 Connector type: 2 x 6 pins Pin no. Connection name Colour To/from 1 +24V Yellow AZ motor driver 2 Ground Black AZ motor driver 3 +5V Red Not used 4 Ground Black Not used 5 +18V Orange Up/Down converter unit 6 +8V Red Up/Down converter unit 7 -15.5V Brown Up/Down converter unit 8 Ground Black Up/Down converter unit 9 +18V DC Orange Tracking receiver unit 10 +8V DC Red Tracking receiver unit 11 -15.5V DC Brown Tracking receiver unit 12 Ground Black Tracking receiver unit Connector no.: P6 Connector type: 2 x 5 pins Pin no. Connection name Colour To/from 1 +18V DC Grey ribbon cable Triplexer/Tsp 2 +8V DC Grey ribbon cable Triplexer/Tsp 3 +8V DC Grey ribbon cable Triplexer/Tsp 4 No connection Grey ribbon cable Triplexer/Tsp 5 Ground Grey ribbon cable Triplexer/Tsp 6 No connection Grey ribbon cable Triplexer/Tsp 7 Rx data Grey ribbon cable Triplexer/Tsp 8 Tx data Grey ribbon cable Triplexer/Tsp 9 No connection Grey ribbon cable Triplexer/Tsp 10 No connection Grey ribbon cable Triplexer/Tsp 5.1.3.8 STEP MOTOR DRIVER PART no.: 629362 P2 29362-50 P1 Connector no.: P1 Connector type: 2 x 4 pins Pin no. Connection name Colour To/from 1 Phase A Green TSP 2 Ground Black TSP 3 Phase B Blue TSP 4 Phase C Violet TSP 5 No connection 6 Phase D Grey TSP 7 +24V DC Yellow SMPS 8 Ground Black SMPS PAGE 5-13 9905

Inmarsat B Connector no.: P2 Connector type: 2 x 3 pins Pin no. Connection name Colour To/from 1 Phase A Blue Step motor 2 No connection 3 Phase B Red Step motor 4 Phase C Green Step motor 5 No connection 6 Phase D Black Step motor 5.1.3.10 DC MOTOR DRIVER PART no.: 634686 Connector no.: X1 Connector type: 2 x 5 pins Pin no. Connection name Colour To/from 1 WC Orange Motor 2 Ground Black Motor 3 WB Red Motor 4 H3 White Motor 5 WA Brown Motor 6 H2 Blue Motor 7 No connection 8 H1 Grey Motor 9 +5V Violet Motor 10 Ground Black Motor Connector no.: X2 Connector type: 2 x 4 pins Pin no. Connection name Colour To/from 1 No connection 2 Ground Green TSP 3 No connection 4 Break Violet TSP 5 Ref White TSP 6 Phase Grey TSP 7 +24V DC Yellow SMPS 8 Ground Black SMPS PAGE 5-14 9905

Inmarsat B 5.1.3.11 TILT SENSOR PART no.: 629366 P1 29366-50 Connector no.: P1 Connector type: 2 x 4 pins Pin no. Connection name Colour To/from 1 No connection 2 X output Blue TSP 3 Y output Violet TSP 4 Ground Black TSP 5 +18V DC Orange Fluxgate compass 6 +8v DC Red Fluxgate compass 7 -15.5V DC Brown Fluxgate compass 8 Ground Black Fluxgate compass 5.1.3.12 FLUXGATE COMPASS PART no.: 629369 P2 P3 29369-50 Connector no.: P2 Connector type: 2 x 6 pins Pin no. Connection name Colour To/from 1 +18V DC Orange Tilt sensor 2 +8V DC Red Tilt sensor 3 -15.5V DC Brown Tilt sensor 4 Ground Black Tilt sensor 5 Not used 6 +12V DC Yellow Rate sensor EL 7 Not used 8 Ground Black Rate sensor EL 9 Not used 10 +12V DC Yellow Rate sensor CE 11 Not used 12 Not used PAGE 5-15 9905

Inmarsat B Connector no.: P3 Connector type: 2 x 5 pins Pin no. Connection name Colour To/from 1 +12V DC Test point 2 +5V DC Test point 3 +18V DC Orange SMPS 4 +8V DC Red SMPS 5 -15.5V DC Brown SMPS 6 Ground Ground SMPS 7 Compass x output Violet TSP 8 Compass y output Grey TSP 9 -12V DC Test point 10 Ground Black TSP 5.1.3.13 ZERO-MARK DETECTOR PART no.: 629365 P1 29365-50 Connector no.: P1 Connector type: Molex, 2 x 3 pins Pin no. Connection name Colour To/from 1 Zero mark White TSP 2 Ground Black TSP 3 +8V DC Red SMPS 4 Ground Black SMPS 5 No connection 6 No connection 5.1.3.14 INTERCONNECTION BOARD PART no.: 629349 Connector no.: X3 Connector type: Molex, 2 x 2 pins Pin no. Connection name Colour To/from 1 +40V DC Red SMPS 2 Ground Black SMPS 3 +40V DC Red SMPS 4 Ground Black SMPS PAGE 5-16 9905

Inmarsat B 5.2 TRANSCEIVER UNIT 5.2.1 MODULE LOCATION CSP/VDP MODULE LSD/HSD COMBI MODEM 629347 630953 PAX MODULE 631593 SPS MODULE 631531 SMI MODULE 631800 32332C PAGE 5-17 9936

Inmarsat B 5.2.2 CONNECTORS AND SOFTWARE LOCATION Connectors: Connector no.: X1 Connector type: Micro match, 20 pins Pin no. Connection name To/from 1 Ground ALL boards 2 ADDR0 ALL boards 3 ADDR1 ALL boards 4 ADDR2 ALL boards 5 ADDR3 ALL boards 6 DATA0 ALL boards 7 DATA1 ALL boards 8 DATA2 ALL boards 9 DATA3 ALL boards 10 DATA4 ALL boards 11 DATA5 ALL boards 12 DATA6 ALL boards 13 DATA7 ALL boards 14 STROBE0 ALL boards 15 STROBE1 ALL boards 16 STROBE2 ALL boards 17 STROBE3 ALL boards 18 No connection ALL boards 19 Reset ALL boards 20 Ground ALL boards Connector no.: X2 Connector type: Micro match, 20 pins Pin no. Connection name To/from 1 RS232 TLX RX SMI,PAX,CSP 2 RS232 TLX TX SMI,PAX,CSP 3 RS232 PRN TX SMI,PAX,CSP 4 RS232 GROUND SMI,PAX,CSP 5 RS232 PRN RX SMI,PAX,CSP 6 RS232 +12V SMI,PAX,CSP 7 RS232 -12V SMI,PAX,CSP 8 RS232 PRN CTS SMI,PAX,CSP 9 RS232 MON RX SMI,PAX,CSP 10 RS232 MON TX SMI,PAX,CSP 11 POSITION RX+ SMI,PAX,CSP 12 POSITION RX- SMI,PAX,CSP 13 GYRO RX+ SMI,PAX,CSP 14 GYRO RX- SMI,PAX,CSP 15 GROUND SMI,PAX,CSP 16 +40V SMI,PAX,CSP 17 BUTTON1 SMI,PAX,CSP 18 BUTTON2 SMI,PAX,CSP 19 FACTORY RESET SMI,PAX,CSP 20 GROUND SMI,PAX,CSP PAGE 5-18 9849

Inmarsat B Connector no.: X3 Connector type: Micro match, 20 pins Pin no. Connection name To/from 1 Ground SPS,HSD,LSD,VDP/CSP 2 RCLK SPS,HSD,LSD,VDP/CSP 3 RFS SPS,HSD,LSD,VDP/CSP 4 RDATA SPS,HSD,LSD,VDP/CSP 5 TCLK SPS,HSD,LSD,VDP/CSP 6 TFS SPS,HSD,LSD,VDP/CSP 7 TDATA SPS,HSD,LSD,VDP/CSP 8 RX SIGNAL SPS,HSD,LSD,VDP/CSP 9 TX KEY SPS,HSD,LSD,VDP/CSP 10 MODEM CHANGE SPS,HSD,LSD,VDP/CSP 11 Ground SPS,HSD,LSD,VDP/CSP 12 CLOCK SPS,HSD,LSD,VDP/CSP 13 Ground SPS,HSD,LSD,VDP/CSP 14 NO CONNECTION SPS,HSD,LSD,VDP/CSP 15 NO CONNECTION SPS,HSD,LSD,VDP/CSP 16 ANT RX DATA SPS,HSD,LSD,VDP/CSP 17 ANT TX DATA SPS,HSD,LSD,VDP/CSP 18 NO CONNECTION SPS,HSD,LSD,VDP/CSP 19 NO CONNECTION SPS,HSD,LSD,VDP/CSP 20 Ground SPS,HSD,LSD,VDP/CSP Connector no.: X3A Connector type: Micro match, 20 pins Pin no. Connection name To/from 1 Ground SPS,SMI 2 DATA RX SPS,SMI 3 DATA TX SPS,SMI 4 DATA RTS SPS,SMI 5 DATA CTS SPS,SMI 6 DATA DTR SPS,SMI 7 DATA DSR SPS,SMI 8 PC RX SPS,SMI 9 PC TX SPS,SMI 10 -15V SPS,SMI 11 +15V SPS,SMI 12 +7.5V SPS,SMI 13 -7.5V SPS,SMI 14 Ground SPS,SMI 15 PHONE1+ SPS,SMI 16 PHONE1- SPS,SMI 17 Ground SPS,SMI 18 PHONE2+ SPS,SMI 19 PHONE2- SPS,SMI 20 Ground SPS,SMI PAGE 5-19 9849

Inmarsat B Connector no.: X4 Connector type: Micro match, 8 pins Pin no. Connection name To/from 1 Ground SMI,CSP 2 DATA+ SMI,CSP 3 DATA- SMI,CSP 4 RXAF+ SMI,CSP 5 AF+ SMI,CSP 6 RXAF- SMI,CSP 7 AF- SMI,CSP 8 Ground SMI,CSP Connector no.: X5 Connector type: Micro match, 20 pins Pin no. Connection name To/from 1 Ground SPS,PAX,HSD,LSD,CSP 2 I-SIGNAL-BIT0 SPS,PAX,HSD,LSD,CSP 3 I-SIGNAL-BIT1 SPS,PAX,HSD,LSD,CSP 4 I-SIGNAL-BIT2 SPS,PAX,HSD,LSD,CSP 5 I-SIGNAL-BIT3 SPS,PAX,HSD,LSD,CSP 6 ANAINP SPS,PAX,HSD,LSD,CSP 7 -15V SPS,PAX,HSD,LSD,CSP 8 ANAOUT SPS,PAX,HSD,LSD,CSP 9 +15V SPS,PAX,HSD,LSD,CSP 10 +7.5V SPS,PAX,HSD,LSD,CSP 11 +7.5V SPS,PAX,HSD,LSD,CSP 12 Q-SIGNAL-BIT0 SPS,PAX,HSD,LSD,CSP 13 Q-SIGNAL-BIT1 SPS,PAX,HSD,LSD,CSP 14 Q-SIGNAL-BIT2 SPS,PAX,HSD,LSD,CSP 15 Q-SIGNAL-BIT3 SPS,PAX,HSD,LSD,CSP 16 SYMBOL SYNC SPS,PAX,HSD,LSD,CSP 17 TX I-SIGNAL SPS,PAX,HSD,LSD,CSP 18 TX Q-SIGNAL SPS,PAX,HSD,LSD,CSP 19 PABX IRQ SPS,PAX,HSD,LSD,CSP 20 Ground SPS,PAX,HSD,LSD,CSP Connector no.: X6 Connector type: Micro match, 16 pins Pin no. Connection name To/from 1 Ground SPS,PAX 2 DATA RX SPS,PAX 3 DATA TX SPS,PAX 4 DATA RTS SPS,PAX 5 DATA CTS SPS,PAX 6 DATA DTR SPS,PAX 7 DATA DSR SPS,PAX 8 PC RX SPS,PAX 9 PC TX SPS,PAX 10 Ground SPS,PAX 11 PHONE1+ SPS,PAX 12 PHONE1- SPS,PAX 13 Ground SPS,PAX 14 PHONE2+ SPS,PAX 15 PHONE2- SPS,PAX 16 Ground SPS,PAX PAGE 5-20 9849

Inmarsat B Connector no.: X7 Connector type: Micro match, 8 pins Pin no. Connection name To/from 1 Ground CSP,PAX 2 PAX TX CLK CSP,PAX 3 PAX TX SYNC CSP,PAX 4 PAX TX DATA CSP,PAX 5 PAX RX CLK CSP,PAX 6 PAX RX SYNC CSP,PAX 7 PAX RX DATA CSP,PAX 8 Ground CSP,PAX Connector no.: X8 Connector type: 2 pins Pin no. Connection name Colour To/from 1 VB Red Battery pack, CSP 2 Ground Black Battery pack, CSP Connector no.: X36 Connector type: Micro match, 16 pins Pin no. Connection name To/from 1 Ground CSP, FRONT CONNECTOR 2 +40V CSP, FRONT CONNECTOR 3 RS232 Ground CSP, FRONT CONNECTOR 4 RS232 TLX RX CSP, FRONT CONNECTOR 5 RS232 TLX TX CSP, FRONT CONNECTOR 6 RS232 PRN RX CSP, FRONT CONNECTOR 7 RS232 PRN TX CSP, FRONT CONNECTOR 8 RS232 PRN CTS CSP, FRONT CONNECTOR 9 RS232 MON RX CSP, FRONT CONNECTOR 10 RS232 MON TX CSP, FRONT CONNECTOR 11 POSITION RX+ CSP, FRONT CONNECTOR 12 POSITION RX- CSP, FRONT CONNECTOR 13 GYRO RX+ CSP, FRONT CONNECTOR 14 GYRO RX- CSP, FRONT CONNECTOR 15 TX INHIBIT CSP, FRONT CONNECTOR 16 No connection CSP, FRONT CONNECTOR PAGE 5-21 9849

Inmarsat B 5.2.2.1 SPS BOARD PART no.: 631531 X1 X3 X3A X5 X6 D4 31531-56 Software: Component no. Description Spare part no. D4 Receive Synchronization 731520 Connectors: X1, X3, X3A, X5, X6 5.2.2.2 CSP/VDP BOARD PART no.: 630953 X2 X1 X3 X4 X5 X6 X7 30953-56 D16 D15 X8 Software: Component no. Description Spare part no. D15 CSP/VDP Software 732512 D16 CSP/VDP Software 732513 Connectors: X1, X2, X3, X4, X5, X6, X7, X8 PAGE 5-22 9936

Inmarsat B 5.2.2.3 PAX BOARD PART no.: 631593 X1 X2 D19 D20 X5 X6 X7 31593-56 Software: Component no. Description Spare part no. D19 Phone & Fax Software 731523 D20 Phone & Fax Software 731522 Connectors: X1, X2, X5, X6, X7 5.2.2.4 SMI PART no.: 731649 36832 F3 F2 F1 F4 F5 Fuses: Component no. Description Spare part no. F1 Main fuse - 20A 45.665 F2 Fuse for 40V conv. 45.510 F3 Fuse for 40V conv. 45.510 F4 Fuse for 40V conv. 45.510 F5 Fuse for NMEA - 40V 45.722 PAGE 5-23 9936

Inmarsat B 31800D F2 F3 F4 F1 F5 X3 X2 X1 X4 Connectors: X1, X2, X3, X4 5.2.2.5 LSD, HSD FPGA AND COMBI MODEM PART no.: 629347 29346-56 X1 X3 X5 Connectors: X1, X3, X5 HS FPGA MODEM PART no.: 633846 33847-56 PAGE 5-24 9936

Inmarsat B PAGE 5-25 9936 COMBI MODEM PART no.: 629347 29347-56 5.3 HANDSET 5.3.1 SOFTWARE LOCATION PART no.: 630499 30499-56 D4 Component no. Description Spare part no. D4 CU Software 735158 5.4 CONTROL UNIT 5.4.1 SOFTWARE LOCATION PART no.: 633769 33769-56 D5 Component no. Description Spare part no. D5 CU Software 735585

CONTENTS 6 SERVICE INTERFACE 6-1 6.1 ADE 6-2 6.2 ALARM 6-4 6.3 BOOK 6-4 6.4 BUTTONS 6-5 6.5 CAN 6-5 6.6 CASC 6-5 6.7 COURSE 6-7 6.8 CU 6-7 6.9 DATE 6-9 6.10 EXIT 6-10 6.11 GYRO 6-10 6.12 HELP 6-10 6.13 LES 6-11 6.14 LOG 6-11 6.15 MODEM 6-12 6.16 NUMERIC 6-13 6.17 PAX 6-13 6.18 POSITION 6-14 6.19 PRINTER 6-14 6.20 REGION 6-15 6.21 REMARK 6-16 6.22 SES 6-16 6.23 SNU 6-17 6.24 SPEED 6-18 Inmarsat B 9936

CONTENTS Inmarsat B 6.25 SPS 6-18 6.26 STATUS 6-19 6.27 SU 6-20 6.28 TEST 6-20 6.29 TIME 6-22 6.30 VDP 6-23 6.31 VERSION 6-23 9936

with detailed information about the system. The service interface is intended for use with a personal computer running a terminal emulation program like PROCOMM. The connections between the service PC and the transceiver unit and the settings of the terminal program are all described below: Connections The electrical interface is compatible with RS232C. In order to protect it against ground loops, it is isolated by opto-couplers, which makes it ideal for incidental connections. Only 3 wires need to be connected between the terminal and the transceiver unit, labelled as follows: Service RX: Data from PC to transceiver unit Service TX: Data from transceiver unit to PC Serial GND: Common These signals are found in connector X34 (PC/printer port at the rear panel of the transceiver unit). The following table shows the connections to be made to a PC COM port with either a 9- or 25-pin D-SUB connector. Signal X34 PC, 9-pin SUB-D PC, 25-pin SUB-D Service RX 13 3 2 Service TX 14 2 3 Serial GND 15 5 7 Settings Although the terms may differ for different terminals, the PC or terminal emulation program must be set up using the following parameters: Baud rate: 9600 bps Parity: Odd Data bits: 7 Stop bits: 1 Mode: Full duplex Local echo: Off Hand shake: XON/XOFF (software) DTR/DSR: Off RTS/CTS: Off Translation: OFF Emulation: ASCII, TTY, VT52, VT100 or VT220 Before the actual description, each command has a syntax description. This is a single line for each variant of the command. Optional parts are shown in square brackets like this: POS[ITION] which means that the position command may be typed as either POS or POSITION. When a choice of completely different words are available, the vertical bar | is used like this: NORTH|SOUTH which means that the parameter is either NORTH or SOUTH. Parameters with a lot of different values are shown as the type of the parameter in lower case like this:

Inmarsat B PAGE 6-2 9905 longitude As shown, some of the commands have a short-form alias, but the descriptions are in alphabetical order according to the full-length forms. 6.1 ADE Shows the state of the Above Deck Equipment (ADE) or uploads a new program. The following variants are available: Syntax ADE ADE UPLOAD ADE UPLOAD BOOT 6.1.1 ADE If the ADE is not connected, this is shown. Otherwise the state of the ADE is shown as follows: Version The main software version of the controller located in the TSP module. Boot sector The software version of the boot sector for the controller located in the TSP module. This version is primarily for manufacturing purposes. Ready The first few minutes after power-on, the ADE will align the sensors, and this entry will be no. Otherwise it will be yes. Searching While the ADE is searching for a new satellite, this entry will be yes. Otherwise it will be no. Found When the ADE has found a satellite, and is not searching for another, this entry will be yes. Otherwise it will be no. Azimuth The azimuth part of the current antenna pointing direction in degrees:minutes. This value is not valid before the first satellite search has been performed and is not updated while searching. If the position is available, the calculated azimuth follows. Elevation The elevation part of the current antenna pointing direction in degrees:minutes. This value is not valid before the first satellite search has been performed and is not updated while searching. If the position is available, the calculated elevation follows. Tracking The current channel number, in hexadecimal, of the tracking receiver. This will be the Network Co-ordinating Station (NCS) common channel (NCSC) for the current ocean region. A value of 0000 indicates that the first search after power-on has not begun yet. The tracking channel is followed by the output level of the tracking receiver averaged over the last 35 seconds. The level is shown in dB between 0.0 and 50.0 relative to the minimum signal level detectable by the tracking receiver. Receiver The current channel number (hexadecimal) of the main receiver.

Inmarsat B Transmitter The current channel number (hexadecimal) of the transmitter followed by the current or latest power level and whether or not the high-power amplifier (HPA) is enabled. 6.1.2 ADE UPLOAD If it is necessary to update the software in the ADE, this command may be used to transfer a program file from a disk directly to the FLASH memory of the controller on the TSP board. The TTY device must be a PC running a terminal emulation program. The following procedure is used: Type the command ADE UPLOAD and press Return or Enter. If the ADE is not connected you will be notified and returned to a new command prompt. Otherwise, you will be asked to start the upload or press the Escape key to abort the procedure. Please note the following: NOTE The SES is now disabled for normal operation and there is no automatic time-out associated with the procedure. Insert the supplied program disk in the floppy drive, A: or B:, in the following referred to as A:. Start the upload of the file A:TSP.HEX. Using PROCOM for MS-DOS® you have to press the Page-up key, select the ASCII protocol and finally type the file name A:TSP.HEX and press Return or Enter. The file is now being transferred to the Below Deck Equipment (BDE) for validation. A typical program contains approx. 2600 lines and the current line number is displayed during the transfer. If any error is detected, you will be notified and returned to the command prompt after normal operation has been re-enabled. When the transfer to the BDE is complete and found to be valid this will be displayed and the program transferred to the ADE. During this process the percentage done will be displayed. Again, if any error is detected you will be notified and returned to the command prompt after normal operation has been re-enabled. Finally, when all of the program has been transferred to the ADE it will reset itself changing to the new program. During this process the connection to the ADE will be lost for about 20 seconds. After this, normal operation will be re-enabled. In order to assure yourself of the success of the upload, the version of the new program may be checked against the disk label using the ADE command without parameters (refer to 0). 6.1.3 ADE UPLOAD BOOT The ADE program is split into two functional blocks. The primary block deals with the actual control and regulation mechanism and may be changed using the ADE UPLOAD command. The secondary block contains general program code such as the FLASH memory programming algorithm. Even though this block is not likely to change, the ADE UPLOAD BOOT command may be used to do so. The procedure is the same as for the ADE UPLOAD command, except the floppy disk file name is changed to TSPBOOT.HEX. PAGE 6-3 9936

Inmarsat B 6.2 ALARM Shows the state of the indicator output pins in the Alarm connector X35. Syntax ALARM 6.2.1 ALARM The state of the indicators are listed with a logical number, the connector and pin number, the title and the state on or flash or off. The state on is an active low on the pin. Off is high impedance. 6.3 BOOK Shows or changes the contents of the phone book. Syntax BOOK BOOK entry BOOK entry number BOOK entry number “name” BOOK CLEAR BOOK entry CLEAR 6.3.1 BOOK Shows all phone book entries not empty. This command may be used to make a backup of the phone book, i.e. on a disk file. To restore the phone book, simply clear the phone book (refer to 0) and play back the file. 6.3.2 BOOK ENTRY Shows the specified phone book entry. 6.3.3 BOOK ENTRY NUMBER Changes the phone number of the specified phone book entry. The name, if any, will not be changed. 6.3.4 BOOK ENTRY NUMBER “NAME” Changes the phone number and the associated name of the specified phone book entry. The name must be in quotes. 6.3.5 BOOK CLEAR Empties the entire phone book. 6.3.6 BOOK ENTRY CLEAR Empties the specified phone book entry. PAGE 6-4 9905

Inmarsat B 6.4 BUTTONS Shows the state of the distress button input pins in the Alarm connector X35. Syntax BUTTON[S] 6.4.1 BUTTONS The state of each button is shown as either pressed, released or never pressed. Following the state is the associated device, i.e. CU extension 2. 6.5 CAN Shows the state of the CAN data network connected to the Scanbus connector X31 pins 2 and 3. Syntax CAN 6.5.1 CAN The state of the network is shown as follows: Bus error now If the network is currently malfunctioning this entry will be yes. Otherwise it will be no. A malfunctioning network is typically caused by a broken cable or no other devices being attached to it. Bus error count The total number of bus errors since power-on. TX FIFO overrun This entry must be no in order for the SES to communicate on the network. If a TX FIFO memory overrun occurs, this entry will be yes and the network will be disabled. The equipment will have to be switched off and back on. RX main channel The 8 bit main network channel address of the SES. At the moment this value is fixed to decimal 18. RX subchannel For each of the 8 network channel subaddresses of the SES, an indication is given of whether or not anything has been received. If so, alive is stated and otherwise dead. Subaddresses 1, 2 and 3 are used for the control units (refer to 0). At the moment, other subaddresses are unused. 6.6 CASC Shows the state of the Control and Signalling Component (CaSC). This software module handles the satellite signalling syntax and integrates vital information in the SES. Consequently, the state of this software module may be used to diagnose the system. Syntax CASC PAGE 6-5 9905

Inmarsat B 6.6.1 CASC The state of the CaSC is shown as follows: Main state When everything is up and running, this is idle mode. However, other values may occur as follows: reset The initial state at power-on. CaSC stays in this state if for some reason the Inmarsat forward and return IDs are invalid. shutdown Temporary state used during ocean region change and hardware errors. init level 0 Transient state used for initialisation. awaiting sky search parameters CaSC stays in this state until the position is known, the ocean region is valid for the position (ADE elevation >= 0) and the ADE is ready. init level 1 Transient state used for initialisation. init level 2 Transient state used for initialisation. init level 3 Transient state used for initialisation. awaiting sky search Used while the ADE is searching for the satellite. awaiting bulletin board Used after the ADE has found the satellite until the complete bulletin board is received. Usually one or two minutes. init level 4 After the bulletin board has been received, this state is used to validate the selected distress and stand-alone earth stations. awaiting mode Transient state used for initialisation. idle mode The normal working state. type approval mode This state is only used for type approval measurements and will never occur in a normal installation. IDs valid Indicates whether or not the Inmarsat forward and return IDs are valid. Region The current ocean region followed by is invalid if the position is known and the (calculated) ADE elevation is negative. Otherwise is valid. ADE ready Indicates whether or not ADE is ready for use. PAGE 6-6 9905

Inmarsat B Position known Indicates whether or not the position is known. NAVAREA Whenever the position is updated, the associated NAVAREA is calculated. 6.7 COURSE Shows the current course. Syntax COURSE 6.7.1 COURSE Shows the current course in degrees. 6.8 CU Shows the state of the Control Units connected to the Scanbus connector X31. Syntax CU [ALL] CU SC4345|SC4346 CU extension 6.8.1 CU [ALL] Shows the state of all control units. Each CU is shown in a single line with the following format: Extension ?, address ?, type ?, state ?, priority ?, hook ? Extension The local extension in the Inmarsat system. Address The logical address in the Scanbus data network CAN. This address is automatically assigned to each individual unit every time the MES/SES is switched on. Type The hardware type SC4345 or SC4346. State The operational state of the unit translates directly to a specific CAN subchannel (refer to 0): active The current or latest unit being used. CAN subchannel 1. passive Units enabled but not currently used. CAN subchannel 2. disabled Units disabled for call announcements. CAN subchannel 3. Priority The numeric operational priority assigned to the unit. Hook Off or on. PAGE 6-7 9905

Inmarsat B 6.8.2 CU SC4345|SC4346 Shows the state of all control units of a specific hardware type. Refer to 0 for details. 6.8.3 CU EXTENSION Shows the detailed state of a specific control unit with the specified local extension in the Inmarsat system. The following lines of information are shown: Extension The local extension in the Inmarsat system. Channel The physical address in the Scanbus data network CAN. The address consists of an 8 bit fixed main channel and a 3 bit subchannel. The latter is automatically assigned in accordance with the operational state of the CU. Address The logical address in the Scanbus data network CAN. This address is automatically assigned to each individual unit every time the MES/SES is switched on. Type The hardware type SC4345 or SC4346. State The operational state of the unit translates directly to a specific CAN sub channel (refer to 0): active The current or latest unit being used. CAN subchannel 1. passive Units enabled but not currently used. CAN subchannel 2. disabled Units disabled for call announcements. CAN subchannel 3. Priority The numeric operational priority assigned to the unit. Hook Off or on. Display The contents of the display. Each line is shown in quotes. Character codes below 32 and above 126 are shown as a full stop (.). Bar graph The virtual level in the range 0-255 inclusive. Backlight On or off followed by the virtual intensity level in the range 0-255 inclusive. The on/off state is not used by the man/machine interface and is always on. Contrast The virtual contrast level in the range 0-255 inclusive. Earpiece On or off followed by the virtual volume level in the range 0-255 inclusive. Microphone On or off. 9905 PAGE 6-8

Inmarsat B Sounder On or off followed by the virtual volume level in the range 0-255 inclusive. Beeper The virtual volume level in the range 0-255 inclusive. Audio The current audio routing: passive Scanbus audio is disabled and the internal sound generator is routed both to the earpiece and speaker. active Scanbus audio is disabled and the internal sound generator is routed only to the earpiece. connected Scanbus audio is enabled for connection and routed to the earpiece and from the microphone, if on. The internal sound generator is routed only to the earpiece. intercom Scanbus audio is enabled for intercom and routed to the earpiece and from the microphone, if on. The internal sound generator is routed only to the earpiece. loop-back Scanbus audio is enabled for loop-back test and routed from the input to the output. The internal sound generator is routed only to the earpiece. 6.9 DATE Shows or sets the date. Syntax DATE DATE year month day 6.9.1 DATE Shows the current date and time. 6.9.2 DATE YEAR MONTH DAY Changes the date. The parameters are: year The year in the range 1900-2155 inclusive. month The month in the range 1-12 inclusive. day The day of the month in the range 1-31 inclusive. PAGE 6-9 9905

Inmarsat B 6.10 EXIT Ends the service interface. Syntax EXIT EXIT Ends the interface and restores the interface settings to the defaults (). 6.11 GYRO Shows the current gyro heading provided through the NMEA connector X32 pins 8 and 9. Syntax GYRO GYRO RAW 6.11.1 GYRO Shows the heading in degrees:minutes. 6.11.2 GYRO RAW Shows the raw NMEA input until the Escape key is pressed. 6.12 HELP On-line help. Syntax HELP HELP LIST HELP command HELP ALL 6.12.1 HELP Shows command words. The short-form versions are not included. 6.12.2 HELP LIST Lists all commands with a single line syntax description. 6.12.3 HELP COMMAND Shows detailed help about a specific command. 6.12.4 HELP ALL Shows detailed help about all commands. 9905 PAGE 6-10

Inmarsat B 6.13 LES Shows or changes the list of land earth stations. This command is identical to the SES command. Refer to section 0. 6.14 LOG Shows the call log. Syntax LOG LOG count LOG ID number 6.14.1 LOG Shows the latest call log entry. If no call has been logged, this is shown. Otherwise the following is listed: Log entry ID A unique numeric identification of the log entry. Each time a new entry is logged, it will be assigned the previous ID plus 1. The ID number wraps around from 65535 to 0. Start time The date and time when connection was established. Duration The time from connection to disconnection in hours:minutes:seconds, preceeded by the number of days in the odd instance that a connection lasts for 24 hours or more. Service type The type of service used, which is one of the following possibilities: voice Inmarsat B standard voice. voice 9k6 Inmarsat B voice at 9600 bps. Reserved by Inmarsat and not currently used. fax Inmarsat B standard fax. data 9k6 Inmarsat B data at 9600 bps. data 16k Inmarsat B data at 16000 bps. Reserved by Inmarsat and not currently used. data 56k Inmarsat B data at 56000 bps. data 64k Inmarsat B data at 64000 bps. telex Inmarsat B telex. Purpose The purpose of the call, which is one of the following possibilities: normal Standard priority. PAGE 6-11 9905

Inmarsat B distress Distress priority. distress test Distress priority test. Ocean region The name of the region. Earth station The access code of the earth station followed by the name, if available. Addressee The service address of called party. Terminal ID The number of the terminal used. User ID If available, a unique identification of the person having made the call. Termination The Inmarsat standard code for the call termination reason, followed by a short explanation, if known. 6.14.2 LOG COUNT Shows the specified number of latest call log entries. Each entry is shown as described above. 6.14.3 LOG ID NUMBER Shows the call log entry with the specified ID. The entry is shown as described above. 6.15 MODEM Shows the state of the MODEM. Syntax MODEM 6.15.1 MODEM If the modem is not found, this is shown. Otherwise the following is listed: If the MODEM has never been active, i.e. frame-sync has not been obtained, this is shown at the beginning of the list. Input Status of the receiver section is listed as follows: Channel type The current Inmarsat forward channel type. Frame-sync Whether or not reception frame synchronisation is currently obtained. Frame number The logical number of the current/latest frame. 9905 PAGE 6-12

Inmarsat B Output Status of the transmitter section is listed as follows: Channel type The current Inmarsat return channel type. Key active Whether or not the TX KEY signal is active. TX inhibit Whether or not the transmitter is inhibited by the TX-INHIBIT input signal. Test enabled This entry is used only for production testing and will always be no in normal installations. 6.16 NUMERIC Shows or changes the default interpretation of numeric parameters. Syntax NUM[ERIC] NUM[ERIC] DEC[IMAL] NUM[ERIC] HEX[ADECIMAL] 6.16.1 NUMERIC Shows the current numeric default. 6.16.2 NUMERIC DECIMAL Sets the numeric default interpretation to decimal. 6.16.3 NUMERIC HEXADECIMAL Sets the numeric default interpretation to hexadecimal. 6.17 PAX Shows the state of the phone and fax module. Syntax PAX 6.17.1 PAX If the PAX is not found, this is shown. Otherwise the following is listed: Version The software version of the controller. PAGE 6-13 9905

Inmarsat B 6.18 POSITION Shows or sets the current global position. Syntax POS[ITION] POS[ITION] latitude N[ORTH]|S[OUTH] longitude E[AST]|W[EST] POS[ITION] AUTO POS[ITION] AUTO ON|OFF POS[ITION] RAW 6.18.1 POSITION Shows the current position and input source. 6.18.2 POSITION LATITUDE N[ORTH]|S[OUTH] LONGITUDE E[AST]|W[EST] Sets the position manually. The parameters are: latitude The latitude in degrees 0-90 inclusive. north|south The direction of the latitude. longitude The longitude in degrees 0-180 inclusive. east|west The direction of the longitude. 6.18.3 POSITION AUTO Shows whether or not the position may be calculated based on the antenna pointing direction. This will only occur if the NMEA position information is missing and the antenna is locked to a satellite. 6.18.4 POSITION AUTO ON|OFF Specifies whether or not the position may be calculated based on the antenna pointing direction. 6.18.5 POSITION RAW Shows the raw NMEA input until the Escape key is pressed. 6.19 PRINTER Shows the state of the printer interface. Syntax PRINTER 9905 PAGE 6-14

Inmarsat B 6.19.1 PRINTER The following items are listed: Open Whether or not a print job is currently active. Printing Whether or not data is currently being transferred to the printer. Waiting Whether or not an active print job is waiting for the printer to become ready. CTS active Whether or not the hardware pace control is active. CTS changed Whether or not the hardware pace control input has changed since power-on. XON active Whether or not the software pace control is active. XON/XOFF received Whether or not the software pace control has been used since power-on. 6.20 REGION Shows or sets the current ocean region. Syntax REGION REGION region REGION AUTO REGION AUTO ON|OFF 6.20.1 REGION Shows the current ocean region. 6.20.2 REGION REGION Sets the current ocean region. The following numeric and abbreviated regions may be used: 0 AORW Atlantic Ocean Region West 1 AORE Atlantic Ocean Region East 2 POR Pacific Ocean Region 3 IOR Indian Ocean Region 6.20.3 REGION AUTO Shows whether or not the region may be selected automatically based on the position. This will only occur if the satellite signal is lost for a long period of time. 6.20.4 REGION AUTO ON|OFF Specifies whether or not the region may be selected automatically based on the position. PAGE 6-15 9905

Inmarsat B 6.21 REMARK A sequence of command lines may be prepared off-line and downloaded to the service interface. This command may be used to add comments to such a sequence. Syntax REM[ARK] [anything] 6.21.1 REM[ARK] [anything] Does nothing. 6.22 SES Shows or changes the list of earth stations. Syntax SES [ALL] SES ALL region SES ALL ALL SES access SES access region SES access ALL SES access “name” SES access region “name” SES access ALL “name” 6.22.1 SES [ALL] Shows all earth stations in the current ocean region. Each SES is shown in a single line having the following format: Access code A number used globally to identify the SES. Name The title, if any, assigned by the user, in quotes. Capabilities The main operational capabilities of the SES. One or more of the following: backup The SES is distress backup for the NCS. distress The SES can handle real distress calls. no capabilities The SES cannot handle any kind of communication. stand-alone The SES will work in stand-alone mode while the NCS is down. test The SES can handle distress test calls. voice The SES can handle standard voice calls. 9905 PAGE 6-16

Inmarsat B TBD-voice The SES can handle non-standard voice calls. This option is reserved by Inmarsat for future use. 6.22.2 SES ALL REGION Shows all earth stations in the specified region. Refer to the REGION command (0) to get a list of the available regions. 6.22.3 SES ALL ALL Shows all earth stations in all regions. 6.22.4 SES ACCESS Shows the specified earth station in the current region. 6.22.5 SES ACCESS region Shows the specified earth station in the specified region. Refer to the REGION command (0) to get a list of the available regions. 6.22.6 SES ACCESS ALL Shows the specified earth station in all regions. 6.22.7 SES ACCESS “NAME” Changes the name of the earth station in the current region. The name must be in quotes. 6.22.8 SES ACCESS REGION “NAME” Changes the name of the earth station in the specified region with the specified access code. The name must be in quotes. Refer to the REGION command (0) to get a list of the available regions. 6.22.9 SES ACCESS ALL “NAME” Changes the name of the earth station in the specified region with the specified access code. The name must be in quotes. 6.23 SNU This command is reserved for handling future SNU implementations. It will show the state of the Scanbus Node Units connected to the Scanbus connector X31. At the moment, it simply shows that no SNUs are known. Syntax SNU [ALL] SNU 0|1|2|3 PAGE 6-17 9905

Inmarsat B 6.23.1 SNU [ALL] Shows the state of all node units. 6.23.2 SNU 0|1|2|3 Shows the state of a specific node unit. 6.24 SPEED Shows the current speed. Syntax SPEED 6.24.1 SPEED Shows the current speed in knots. 6.25 SPS Shows the state of the signal path and synthesizer module. Syntax SPS 6.25.1 SPS If the SPS is not found, this is shown. Otherwise the following is listed: Input Status of the receiver section is listed as follows: Channel type The current Inmarsat forward channel type. Filter clock The input clock frequency of the switched-capacitor filter. Cut-off frequency The cut-off frequency of the switch-capacitor filter. Cut-off uses VCO Whether or not the clock frequency of the switched-capacitor filter is generated by the VCO of the synthesizer or just the reference divider. Cut-off locked Whether or not the clock frequency synthesizer for the switched-capacitor filter is locked. Intermediate locked Whether or not the intermediate frequency synthesizer is locked. Polling enabled This entry is used for development and will always be yes in normal installations. Signal/noise ratio The base-band signal to noise ratio measured by the digital signal processor (DSP). 9905 PAGE 6-18

Inmarsat B OCXO error The precision of the master oscillator in ppm measured by the DSP relative to the received symbol rate. DSP version The software version of the DSP. Output Status of the transmitter section is listed as follows: Channel type The current Inmarsat return channel type. Filter clock The input clock frequency of the switched-capacitor filter. Cut-off frequency The cut-off frequency of the switch-capacitor filter. Cut-off uses VCO Whether or not the clock frequency of the switched-capacitor filter is generated by the VCO of the synthesizer or just the reference divider. Cut-off locked Whether or not the clock frequency synthesizer for the switched-capacitor filter is locked. Intermediate locked Whether or not the intermediate frequency synthesizer is locked. 6.26 STATUS Shows the main status of the system. Syntax STATUS 6.26.1 STATUS Shows the most important status of the system. One of the following lines are shown: System is idle The system is ready to be used for communication. Inmarsat IDs are invalid This unit has not been initialised with a proper pair of Inmarsat identification numbers. ADE is disconnected The BDE is not communicating with the ADE. Refer to the self-test for additional information. ADE is not ready The ADE is aligning the sensors. This occurs in the first few minutes after power-on. ADE is searching The ADE is searching for a satellite. This occurs after power-on and whenever the ocean region has been changed or the signal has been lost for more than 130 seconds. Bulletin board is invalid The bulletin board is being updated. PAGE 6-19 9905

Inmarsat B Position is missing The position has never been entered manually or has been lost from the NMEA position input. Region is invalid The current position indicates that the satellite of the current ocean region is below the horizon. Voice communication in progress A voice call is currently in progress. FAX communication in progress A FAX call is currently in progress. Data communication in progress A data call is currently in progress. TELEX communication in progress A TELEX call is currently in progress. 6.27 SU Shows the ratio between valid and invalid received signal units. Syntax SU 6.27.1 SU Shows the ratio between signal units received with valid and invalid cyclic redundancy check (CRC). The value is the result of the latest 100 signal units received. 6.28 TEST Executes the self-test. Syntax TEST [WARN] TEST sequence [WARN] TEST LIST TEST number TEST CLEAR The self-test is built around a series of primitive tests each associated with a limited part of the equipment. Each of these tests is described below. Sequences of tests are used to test major equipment blocks such as the entire ADE. All tests are non-destructive, i.e. the self-test may be executed at any time without affecting system performance. Each of the tests results in a test code. Basically, three types are used: passed, warning, and failed. Passed and failed are unique codes whereas warnings are a little more elaborate: 1 - OK The test has passed. 2 - FAILED The test has failed. 3 - target not found Warning indicating that the item to be tested is missing. This has been detected by a previous test in a sequence. 9905 PAGE 6-20

Inmarsat B 4 - target not used Warning indicating that the item to be tested is not used. 5 - input static Warning indicating that the item to be tested has never been activated, i.e. the CTS signal in the printer interface. 6 - wrong state Warning indicating that the item to be tested is not in the right state for the test, i.e. the antenna direction cannot be tested before the first or current search has ended. 6.28.1 TEST [WARN] Runs the complete system self-test sequence (refer to 0). If the WARN parameter is specified warnings are listed. Otherwise, only failed tests are shown. 6.28.2 TEST SEQUENCE [WARN] Runs the specified self-test sequence. If the WARN parameter is specified warnings are shown, otherwise, only failed tests. The following sequences are available: ALL The entire system. ADE The entire ADE. ADERX The receiver path of the ADE. ADETX The transmitter path of the ADE. ADECONTROL The control and interfaces and sensors of the ADE. BDE The entire BDE. BDERX The receiver path of the BDE. BDETX The transmitter path of the BDE. BDECONTROL The control and interfaces of the BDE. MODEM The MODEM module. POST The power-on self-test. RX The entire receiver path. SPS The SPS module. PAGE 6-21 9905

Inmarsat B TX The transmitter path. 6.28.3 TEST LIST Runs all primitive tests separately. 6.28.4 TEST number Runs a specific primitive test. 6.28.5 TEST CLEAR Resets the error states memorised by the system, i.e. battery backup failed. 6.29 TIME Shows or sets the time. Syntax TIME TIME hour minute [second] TIME hour:minute[:second] TIME ON TIME OFF 6.29.1 TIME Shows the current date and time. 6.29 TIME HOUR MINUTE SECOND Changes the time of day. The parameters are: hour The hour in the range 0-23 inclusive. minute The minute in the range 0-59 inclusive. second Optional second in the range 0-59 inclusive. If the parameter is missing, zero is assumed. 6.29.3 TIME HOUR:MINUTE:SECOND As above except the parameters are separated by colon instead of space. 6.29.4 TIME ON Shows the time since last power-on in days (if any) hours:minutes:seconds. 9905 PAGE 6-22

Inmarsat B 6.29.5 TIME OFF Shows the time since last power-off in days (if any) hours:minutes:seconds. 6.30 VDP Shows state of the Voice and Data Processor on the CSP/VDP module. Syntax VDP 6.30.1 VDP If the VDP is not working, this is shown. Otherwise the following is listed: Reception The current reception mode of operation, which is one of the following possibilities: disabled - The VDP is not involved in the current operation. voice-9k6 - Inmarsat B optional voice. voice-16k - Inmarsat B standard voice. fax-9k6 - Inmarsat B fax. data-9k6 - Inmarsat B standard data. data-16k - Inmarsat B optional data. data-56k - Inmarsat B derated high-speed data. data-64k - Inmarsat B high-speed data. Transmission The current transmission mode of operation. The possible modes are identical to those listed for reception. 6.31 VERSION Shows the software version of the system co-ordinating processor. Syntax VER[SION] 6.31.1 VERSION Shows the software version of the control and signal processor (CSP) located on the CSP/VDP module. This processor is the one running the service interface. PAGE 6-23 9905

7-3 7.9 DISTRESS BUTTON 2 7-3 7.10 TELEX INPUT 7-3 7.11 PRINTER INPUT 7-4 7.12 ADE INPUT 7-4 7.13 NMEA POSITION INPUT 7-5 7.14 SERVICE INPUT 7-5 7.15 NMEA GYRO INPUT 7-5 7.16 PRINTER ON-LINE 7-6 7.17 HEADING KNOWN 7-6 7.18 POSITION KNOWN 7-6 7.19 OCEAN REGION VALID 7-7 7.20 CONTROL UNIT FOUND 7-7 7.21 SCANBUS DATA TRANSMISSION 7-7 7.22 SCANBUS DATA RECEPTION 7-7 7.23 TU BUS 7-8 7.24 MODEM FOUND 7-8 9936 Inmarsat B