Pt. Lobos INSTALLATION AND OPERATION MANUAL SEA TEL MODEL TAC-92C/M TRACKING ANTENNA CONTROLLERS This manual applies to the following software versions: TAC-92 C/M Version 2.73 or later 2494 PCU Version 2.50 or later 3294 PCU Version 1.30 or later 2095 PCU Version 3.00 or later Sea Tel, Inc. 1035 Shary Court. Concord, California 94518 Tel: (925) 798-7979 Fax: (925) 798-7986 Email seatel@seatel.com Internet www.seatel.com Table of Contents 1. DESCRIPTION AND TECHNICAL DATA 1 1.1. CHARACTERISTICS 1 1.2. DAC-97 FUNCTIONAL DESCRIPTION 1 1.3. DAC-97 TECHNICAL SPECIFICATIONS 2 1.3.1. General 2 1.3.2. Front Panel 2 1.3.3. Rear Panel 2 1.3.4. RF Tracking Input 3 1.3.5. RS-232 Monitor and Control Interface 3 1.3.6. NMEA Interface 3 1.3.7. External AGC Input 3 1.3.8. Terminal Mounting Strip 3 1.3.9. Environmental Conditions 3 2. INSTALLATION 4 2.1. TERMINAL MOUNTING STRIP CONNECTIONS 4 2.2. PEDESTAL INTERFACE CONNECTIONS 4 2.3. SHIPS GYRO COMPASS CONNECTIONS 4 2.4. AGC TRACKING CONNECTIONS 4 2.5. NMEA CONNECTIONS 5 2.6. MONITOR AND CONTROL CONNECTIONS 5 2.7. SYSTEM CHECK-OUT 6 2.7.1. ACU / ANTENNA SYSTEM CHECKOUT 6 2.7.2. SET CONFIGURATION PARAMETERS 6 2.7.3. NMEA GPS CHECKOUT 7 2.7.4. AUXILIARY SERIAL PORT CHECKOUT 7 3. OPERATION 8 3.1. NORMAL SYSTEM OPERATION 8 3.2. KEYBOARD ENTRY 9 3.3. STATUS LEDS 10 3.3.1. TRACKING LED 10 3.3.2. SEARCHING LED 10 3.3.3. UNWRAP LED (limited azimuth systems only) 10 3.3.4. ERROR LED 10 3.4. TRACKING OPERATION 11 3.4.1. STEP TRACK OPERATION 11 3.4.2. CONSCAN OPERATION 11 3.4.3. CONSCAN SENSITIVITY ADJUSTMENT 11 3.4.4. AGC INPUT SELECTION 11 3.4.5. C/Ku BAND SELECTION 12 3.4.6. SEARCHING OPERATION 13 Table of Contents 3.4.7. SEARCH 1 13 3.4.8. SEARCH 2 13 3.4.9. SEARCH INCREMENT 13 3.4.10. SEARCH LIMIT 14 3.4.11. SEARCH DELAY 14 3.4.12. AUTO THRESHOLD SETTINGS 14 3.4.13. STEP DELAY 14 3.5. AUTO POLARIZATION OPERATION 15 3.5.1. 24V DC POLANG ALIGNMENT 15 3.5.2. 5V SERVO POLANG ALIGNMENT 16 3.5.3. LINEAR / CIRCULAR (HCDC) POLANG ALIGNMENT 17 3.5.4. TX POLARITY SETUP 17 3.6. FUNCTION SUMMARY 18 3.6.1. SHIP DISPLAYS 19 3.6.2. SATELLITE DISPLAYS 19 3.6.3. ANTENNA DISPLAYS 20 3.6.4. MODE DISPLAYS 20 3.6.5. REMOTE PCU CONTROL 25 4. MAINTENANCE 26 4.1. PEDESTAL CONTROL UNIT CONFIGURATION 26 4.2. DISPLAY OFFSET ADJUSTMENTS 26 4.3. ANTENNA PEDESTAL OFFSET ADJUSTMENT 27 4.4. ANTENNA POSITION ERROR MONITORING 27 4.5. OPEN LOOP SENSOR TEST 28 4.6. OPEN LOOP MOTOR TEST 28 4.7. DEFAULT SETUP PARAMETERS - XX96 XX97 29 4.8. MODEL CONFIGURATION PARAMETERS 29 4.9. TROUBLE SHOOTING GUIDE. 30 4.9.1. DAC-97 DISPLAYS "REMOTE NOT RESPONDING" 30 4.9.2. HEADING DISPLAYS INCRORRECTLY 31 5. DRAWINGS 34 1. DESCRIPTION AND TECHNICAL DATA This manual describes the Sea Tel Model DAC-97 shipboard Tracking Antenna Control Unit and provides installation and operating instructions. The DAC-97 is an all digital version of Sea Tel's proven line of TAC-92 Antenna controllers. Throughout this manual are several documents that reference TAC-92 components since most all of the hardware has remained unchanged. 1.1. CHARACTERISTICS The DAC-97 Antenna Control Unit (ACU) communicates via an RS422 serial data link with the Pedestal Control Unit (PCU) located at the antenna. For unlimited azimuth pedestals, the RS422 link is coupled to the PCU via RF multiplexers. The Pedestal Control Unit stabilizes the antenna against the ship's roll, pitch, and turning motions. The DAC-97 ACU is the operator interface to the PCU and provides the user with a choice of positioning commands to point the antenna, search commands to find the satellite signal and tracking functions to maintain optimum pointing. The DAC-97 can incorporate a variety of signal strength receivers for tracking purposes. 1.2. DAC-97 FUNCTIONAL DESCRIPTION The DAC-97 is housed in a standard 19-inch rack mount enclosure. The front panel contains a row of function keys used to select the desired information to be displayed and an array of numeric data entry keys for changing parameters or commanding the antenna functions. Data is displayed on a bright 40 character Vacuum Fluorescent display making it easy to read in all ambient light conditions. The DAC-97 can be mounted on chassis slides allowing easy access to all internal electronics. All external connections are brought out through three D-Subminiature connectors mounted on the rear panel. Flexible ribbon cable extends these connections to a terminal-mounting strip mounted on the rear of the rack enclosure separating the ship wiring from the Antenna Control Unit. The DAC-97 allows the use an internal flux gate compass, external flux gate compass or a shipboard gyrocompass as the long-term azimuth reference. The DAC-97 will accept a Step- by-step or 1:1, 36:1, 90:1 or 360:1 Synchro gyro interface. The DAC-97 automatically calculates the Elevation, Azimuth and Polarization pointing angles (POLANG) based on the ships Latitude, Longitude and the desired Satellite Longitude position. A programmable pattern search will automatically scan the area for a desired satellite if no signal is found. These two features make locating a new satellite very easy. A serial communications Monitor and Control (M&C) interface allows external control of the DAC-97 from a PC, ASCII terminal, or telephone modem. This interface can also be used to update the ships Latitude and Longitude information from a GPS or LORAN system or update heading from a flux gate or gyro using the NMEA interface standard. The DAC-97 will accept signal level information for tracking purposes from one of three internal receiver options or an external receiver. The standard internal receiver is a dual input full coverage wide band video receiver for tracking video transponders in all TVRO and most data applications. Two narrow band beacon-tracking receivers are available with either 70 MHz or L-BAND inputs to allow tracking on a satellite beacon or narrow band data carrier. 1.3. DAC-97 TECHNICAL SPECIFICATIONS 1.3.1. General Physical Dimensions: 3.5 x 19" x 14" Mounting: 2 Unit high Rackmount Input Voltage: 110/220 VAC, 50/60 Hz Power Requirements: 100-Watts maximum Fuses: 2 Amp 110v input, both lines fused 1 Amp 220v input, both lines fused 1.3.2. Front Panel Keyboard: 4 Mode Select Keys 14 Numeric Input Keys 2 Up/Down Keys 2 Auxiliary Keys 1 Reset Key AlphaNumeric Display: 40 Character (2x20) Vacuum Fluorescent Alpha Numeric Status Indicator Display: 4 LED enunciators 1.3.3. Rear Panel Controls: Power On/Off Voltage Select Connectors: External AGC 37 pin female D-Subminiature Gyro Compass input 25 pin female D-Subminiature RS-232/422 M&C 9 pin male D-Subminiature RS-422 PCU interface 9 pin male D-Subminiature RF Tracking Input Type F female L Band input BNC 70 MHz input AC Input Power IEC type receptacle 1.3.4. RF Tracking Input Wide band TVRO receiver: Frequency Range: 950 - 2050 MHz Detection Bandwidth: 16 MHz Input Level: -65 to -20 dBm LNB switching: 13/18 volt band select switching Narrow Band SCPC receiver: Frequency Range: 950 - 1750 MHz (L band SCPC) 60 - 80 MHz (70 MHz SCPC) 110 - 170 (140 MHz SCPC) Detection Bandwidth: 30 kHz 1.3.5. RS-232 Monitor and Control Interface Communications Parameters: 4800/9600 Baud, 8,N,1 Device Type DTE Interface Protocol RS-232 or RS-422 Interface Connector DE9P (J11) 1.3.6. NMEA Interface Communications Parameters: 4800 Baud, 8,N,1 Interface Protocol Optically isolated RS-422 Interface Connector DE9P (J11 or J13) NMEA GPS Sentence: GPGLL, LCGLL NMEA Heading Sentence: HCHDM 1.3.7. External AGC Input Voltage Level: 0-5 volts DC Impedance: 1 meg ohms 1.3.8. Terminal Mounting Strip Synchro Interface: 5 screw terminal connections SBS Interface 4 screw terminal connections External AGC 2 screw terminal connections NMEA GPS 4 Screw terminal connections 1.3.9. Environmental Conditions The following requirements apply to equipment installed in weather protected locations. Temperature 0 to 40 degrees C Humidity Up to 100% @ 40 degrees C Non-condensing 2. INSTALLATION The following instructions describe the installation procedures for the DAC-97 Tracking Antenna Controller. The installation of the DAC-97 is outlined in the Pedestal Installation and Operation manual and may already have been performed. 2.1. TERMINAL MOUNTING STRIP CONNECTIONS 1. Connect the 25 pin ribbon cable from the Terminal Mounting Strip to J3 on the DAC-97. 2. Connect the 9 pin ribbon cable or round NMEA serial cable from the Terminal Mounting Strip to J13 (if exists) or J11 on the DAC-97. 3. If a two wire External AGC cable is attached to the Terminal Mounting Strip, connect the 37 pin connector to J2 on the DAC-97. 2.2. PEDESTAL INTERFACE CONNECTIONS Connect the Serial Control Cable, between J1 on the rear of the DAC-97 and the 9 pin D Sub connector on the base multiplexer mounted in the rear of the rack. 2.3. SHIPS GYRO COMPASS CONNECTIONS Connect the ship's gyrocompass or gyro compass repeater output to the Terminal Mounting Strip. Use TB3 for a Step-by- Step gyro compass and match the connections to A, B, C and COM with the gyro compass output. Use TB1 for a Synchro gyrocompass and match the connections to R1, R2, S1, S2 and S3 with the gyro compass output. Refer to Appendix A if interface problems arise. 2.4. AGC TRACKING CONNECTIONS When using the internal receiver, connect the appropriate RF or IF cable from a splitter or directional coupler to IN A or IN B on the rear panel of the DAC-97. Refer to the system block diagram in the pedestal Installation and Operation manual. For external AGC, connect a cable between the AGC or TM output of the master receiver or modem and the terminals labeled X1, X2 on TB2 of the Terminal Mounting Strip or to the two wire cable leading from J2. Connect the negative lead to X2 or the Brown wire. 2.5. NMEA CONNECTIONS The NMEA port allows automatic Latitude, Longitude and heading updates from a GPS receiver or gyrocompass. For GPS input, connect the 4 wires from the GPS receiver to connector J13 or J11 on the back of the DAC-97 as shown in drawing 112791. For heading input, connect pins 1 & 2 only (RX+, RX-) to the gyrocompass. To enable the interface, select the system TYPE parameter under the MODE/SETUP display and verify that type 8 or a combination that includes 8 is selected. NOTE: The DAC-97 is available with one or two NMEA/M&C ports installed at J13 and J11. If two ports are installed, use J13 for the NMEA input. If two NMEA inputs are used (heading and GPS) use J13 for the heading input. If only one port is installed, then only M&C or NMEA GPS functions are available and only one at a time. 2.6. MONITOR and CONTROL CONNECTIONS The Monitor and Control port allows external control from a modem, ASCII terminal or PC. Sea Tel supplies a windows based antenna control program called PCDAC which allows choosing satellites and tracking functions from a pull down menu, simultaneous display of all antenna functions and dialog box control of tracking and searching functions. Contact a Sea Tel sales representative for details on obtaining a copy. The DAC-97 is wired as a DTE device for direct connection to a modem. For connection to another DTE device such as a terminal or PC, a null modem cable as shown in drawing 110762 is required. Connect the null modem cable between J11 on the back of the DAC-97 and the ASCII terminal or PC serial interface port. Set the terminal or PC to 4800 baud, 8 bits, no parity (9600 baud operation is available on the Aux Serial Board only by installing a jumper at D1). Enable the interface by selecting the system TYPE parameter under the MODE/SETUP display and verify that type 8 or a combination that includes 8 is selected. See DWG 114493 in Section 4.5 for details on the serial commands available. NOTE: The DAC-97 is available with one or two NMEA/M&C ports installed at J13 and J11. If two ports are installed, use J13 for the NMEA input. If two NMEA inputs are used (heading and GPS) use J13 for the heading input. If only one port is installed, then only M&C or NMEA GPS functions are available and only one at a time. 2.7. SYSTEM CHECK-OUT The following procedures provide instructions for performing pre-operational checkout of the system. 2.7.1. ACU / ANTENNA SYSTEM CHECKOUT 1. Turn on the main power switch at the rear panel. 2. Press RESET on the ACU front panel to initialize the system. Verify the display shows "SEA TEL INC - MASTER" and the ACU software version number. Wait 6 seconds for the display to change to "SEA TEL INC - REMOTE" and the PCU software version number. If the display shows "REMOTE NOT RESPONDING" Refer to Appendix A in Section 4. 3. Press the ANTENNA key twice to select the AZIMUTH entry display. Press the UP and DOWN keys and observe that the azimuth display changes in the correct response to the keys. 2.7.2. SET CONFIGURATION PARAMETERS 1. Press the MODE key several times until the GYRO TYPE display appears. If MODE will not advance beyond the REMOTE AUX display, key in 7979 and press ENTER. At the GYRO TYPE display, key in the appropriate Gyro Compass interface type indicated below and press ENTER: 0 for NO Gyro connection (Internal Flux Gate) 2 for Step-By-Step gyro or NMEA gyro 360 for 360:1 Synchro with SBS Converter 362 for 360:1 Synchro with S/D Converter 90 for 90:1 Synchro with S/D Converter 36 for 36:1 Synchro with S/D Converter 1 for 1:1 Synchro with S/D Converter 2. Press the ENTER key again to select the POLANG TYPE. Key in the appropriate Polang type indicated below: 0 for no polang 9 for 24v manual polang with numeric display 72 for 24v auto polang with numeric display 64 for 24v auto polang with HORZ/VERT display 68 for Lin/Circ feed with auto polang 80 for 5v auto polang with HORZ/VERT display 112 for 5v auto polang with numeric display 3. Press ENTER several more times to select "SAVE NEW PARAMETERS" display. Press UP arrow then ENTER to save the new parameters. NOTE: if the parameters are not saved, they will be lost when the DAC-97 is RESET or turned off. 4. Press the SHIP key 4 times to select the HEADING entry display. Enter the correct ships heading reported by the bridge by pressing the appropriate keys on the numeric entry pad. Press ENTER to save this data. 5. Observe that the heading display changes in the correct direction as the ship turns. If the heading display changes incorrectly or the red ERROR LED illuminates on the front panel, check the configuration parameters below and refer to Appendix B. 2.7.3. NMEA GPS CHECKOUT 1. When a NMEA GPS receiver is connected to J13 or J11, the NMEA LED on the AUX SERIAL PORT ADAPTOR (ASPA) PC board will illuminate each time a NMEA message is received. The GLL LED will illuminate each time a GPGLL or LCGLL message is received. Observe the NMEA and GLL LED's and confirm they are flashing about once every 2 seconds (when the system is first powered up, the GLL LED may not appear for several minutes while the GPS receiver is acquiring the necessary satellite signals). 2. If the GLL LED is illuminated constantly, this indicates the message in not being transferred to the DAC-97 board because the system type does not include the 8 setting. 2.7.4. AUXILIARY SERIAL PORT CHECKOUT When a remote computer or terminal is connected to J11, the DISK LED will illuminate steady when a message is being received and will extinguish when the message is transferred to the TAC-92. To test this connection, set the remote terminal to 4800,N,8,1 and send an "A". The DISK LED should illuminate. Send a Carriage Return ($0D), the DISK LED should extinguish. Send a "V", the TAC-92 should respond with the ACU version number. A list of the commands available through the serial port is shown in DWG 114493 in Section 5 3. OPERATION 3.1. NORMAL SYSTEM OPERATION Normal operation of the system from a cold start involves the following steps: 1. Turn on the AC Power switches for the ACU and the Radio packages. Press the RESET button on the ACU front panel to initialize the system and show the current Master Unit version number. Wait 1-2 minutes for the antenna to initialize. After initialization the display will show the Remote Unit version number. 2. Press SHIP to select the ship's position displays. Press SHIP again to select the LAT entry mode. Key in the ships Latitude to the nearest degree. Pressing the decimal key can enter tenths of a degree. Use the NS/EW key to set the correct hemisphere. Press ENTER to save the entry. Press ENTER again to select the LON entry mode. Key in the ships Longitude. Press ENTER to save the entry. Press ENTER again to select the HDG entry mode. Key in the ships heading if using an SBS or 36:1, 90:1 or 360:1 synchro gyro interface. Do not enter a ships heading for systems using 1:1 synchro, NMEA heading or flux gate reference. 3. Press SAT twice to select the Satellite entry mode. Key in the desired satellite longitude and press ENTER. The ACU will automatically calculate the correct elevation and azimuth pointing angles and move the antenna to the appropriate position. 4. Tune the internal or external receiver to the appropriate frequency to receive the satellite signal. 5. If no signal is found: Select the SEARCHING function under the MODE/CONTROL display. Use the UP key to turn SEARCHING on. The ACU will automatically set the AGC threshold and move the antenna in a spiral pattern. The search movement will stop when the ACU receives a signal above the threshold and automatically begin tracking. If AUTO THRESHOLD is disabled, you will need to manually set the threshold under the SAT display before beginning the search operation. 6. When a satellite signal is found: Manually peak the signal by selecting the AZ and EL functions under the ANTENNA display and adjusting the antenna position for peak signal strength using the up/down keys. 7. Adjust the antenna polarization by selecting the POL function under the ANTENNA display. Select the orientation (HORZ, LHCP, VERT, RHCP) by pressing the NS/EW key. Polang adjustment is automatic on most system configurations. Refer to Section 3.6 for a detailed description of polarization setup, adjustment and operations. 8. If AUTO THRESHOLD is not used, drive the antenna up or down in elevation until the AGC reading is at a minimum. Set the AGC threshold between the minimum and maximum values. Drive the antenna back in elevation to receive a strong signal. 9. For automatic peaking and tracking of the satellite, turn TRACKING on by pressing the AUX1 key or by selecting the TRACKING function under the MODE display and pressing the UP key. The TRACKING LED should be on and the signal should quickly reach a peak value. See section 3.3 for a detailed description of the tracking functions available. Operation from this point on is automatic and will continue unattended until: A. AC power to the system is interrupted, or B. The satellite signal is blocked by a structure on the ship, or C. The ship sails into an area of insufficient satellite signal level. 3.2. KEYBOARD ENTRY The keyboard entry and operation is very simple and straightforward. Pressing any of the 4 function keys located below the VF display, enables the display of all the information associated with that function. Pressing the ENTER Key or the function key again, enables the first display to be modified. This is called the entry mode. Subsequent depressions of the ENTER key or function key again cycle the selected display for modification. A selected display can be overwritten by pressing the desired number keys or it can be incremented and decremented with the up/down keys. Pressing the decimal point allows fractional entries to be made. Pressing C clears the display to correct errors. When satisfied with the entry, press ENTER again to save the information and proceed to the next function. 3.3. STATUS LEDS There are 4 status indicator LEDs on the front panel. They give the operator a continuous display of the major operating sates of the DAC-97 Tracking Antenna Controller. The function of each LED is described below. 3.3.1. TRACKING LED The Tracking LED illuminates when the TRACKING mode is enabled and the received AGC level is above the THRESHOLD setting. The tracking LED will flash if TRACKING is enabled and the AGC level is below threshold. The tracking LED will extinguish and tracking will be suspended if the system goes into SEARCH, automatic UNWRAP or any antenna movement commands are issued. Tracking can be turned ON and OFF with the AUX1 key. 3.3.2. SEARCHING LED The Searching LED performs two functions. If illuminated steady, it indicates that the ACU is performing a systematic pattern search for a satellite signal. If the LED is flashing, it indicates that the ACU is moving the antenna to a predetermined position and all tracking operations will be suspended until the new position is achieved. 3.3.3. UNWRAP LED (limited azimuth systems only) The UNWRAP LED is illuminated and the cable unwrap function initiated, for limited azimuth systems only, whenever the antenna moves within 5 degrees of either end stop (90 and 630 degrees relative). Cable UNWRAP suspends any tracking operations, flashes the SEARCHING LEDand targets the antenna plus or minus 360 degrees from its current position. Any ship movements during the unwrap process are monitored and used to correct the final target position of the antenna. 3.3.4. ERROR LED The ERROR LED is illuminated and will remain illuminated whenever an error is detected. Select ERROR in the MODE/STATUS display to view the error condition. Press UP arrow in this display to clear the error and the LED. Refer to Section 3.8.4 for a description of the error codes. 3.4. TRACKING OPERATION There are two modes of tracking (Step Track and Conscan) and four sources of AGC tracking information available (EXT RCVR, INA, INB and IF). Each system is described below: 3.4.1. STEP TRACK OPERATION Step track keeps the antenna peaked at the optimum position by making small trial movements of the antenna and optimizing the received signal level. The size of the trial steps is adjusted with the EL STEP SIZE and AZ STEP SIZE parameters under the MODE/SETUP display. The recommended STEP SIZE setting for step track is 1/4 the antenna 1 dB beam width. The signal level is integrated at each new position for the time specified by the STEP INTEGRAL parameter. Units are in cycle updates of 1/40 second. A setting of 0 disables Step Track and enables Conscan. The TRACKING parameter must be set to ON to enable Step Track operation. The AUX1 key allows you to toggle tracking ON and OFF from any mode. The AZ and EL STEP SIZE parameters can be set by the Xnnn and Ynnn commands from the M&C control port. 3.4.2. CONSCAN OPERATION Conscan tracking requires the internal Conscan Tracking Controller option and a special feed assembly. Conscan determines the optimum antenna pointing by slightly mispointing the antenna with a rotating lens or eccentric feed element and monitoring the resulting signal level variation. Movement commands are calculated based on the phase of the signal strength variations relative to the feed disturbance. The STEP INTEGRAL parameter must be set to 0 and the TRACKING function must be set to ON to enable Conscan operation. 3.4.3. CONSCAN SENSITIVITY ADJUSTMENT The tracking sensitivity for the AZ and EL axes are set by the AZ STEP SIZE and EL STEP SIZE parameters under the MODE/SETUP display. Increasing the STEP SIZE number by one reduces the system sensitivity by a factor of 2. Default settings for Ku band are 3-AZ, 3-EL. Default settings for C band are 0-AZ, 1- EL. To change the STEP SIZE parameter, you must enter the desired setting twice within 3 seconds. The AZ and EL STEP SIZE sensitivities can also be set by the Xnnn and Ynnn commands from the M&C control port. 3.4.4. AGC INPUT SELECTION There are four choices of AGC tracking information: External Receiver, VIDEO RF Input A (H/C), VIDEO RF Input B (V/Ku), and Narrow Band IF (SCPC). The selection is made by pressing the NS/EW key when the SAT/RCVR mode is selected for entry. EXTERNAL AGC SETTINGS There are no adjustments for external AGC inputs. The allowable input voltage range is 0 to 5 volts with increasing voltage corresponding to increasing signal strength. VIDEO RF RECEIVER TUNING The Video RF inputs (Input A and Input B) can be tuned to channel numbers or specific L, C or Ku band frequencies by selecting the SAT/RCVR display for entry. Entries from 1 to 24 select C band channels. Entries from 950-2000, 3700-4200, 10750-11700 and 11700-12750 select L, C, Europe Ku and North America Ku band frequencies in MHz respectively. Channel selection or fine-tuning in MHz increments can be done with the UP/DOWN keys. IF RECEIVER TUNING The Narrow Band IF or SCPC receiver is tuned to MHz and kHz by two entries. Select the SAT/RCVR mode by pressing the SAT key. Select the IF input using the NS/EW key. Key in the MHz portion and press ENTER. Press "." then key in the kHz portion and press ENTER. For example if the desired IF frequency is 70.015 MHz, key in "70" and press "ENTER", then press ".015" and "ENTER" again. Fine-tuning may be accomplished with the UP and DOWN arrow keys. Press "." to select kHz increments for tuning, press "C" to select MHz increments for tuning. 3.4.5. C/Ku BAND SELECTION For C and Ku band systems the preset tracking parameters for Conscan can be changed in the TRACKING window by pressing the down arrow. The display will indicate which band and tracking parameters are currently selected. For Dual C / Dual Ku band systems, both the tracking parameters and the remote C/Ku relay selection is changed by this selection. 3.5. SEARCHING OPERATION There are two search patterns, SEARCH1 and SEARCH2 and the following searching parameters SEARCH INC, SEARCH LIMIT, SEARCH DELAY and STEP DELAY. 3.5.1. SEARCH 1 SEARCH1 is no longer available on later software releases. 3.5.2. SEARCH 2 SEARCH2 is a two-axis pattern consisting of alternate movements in azimuth and elevation. The size and direction of the movements are increased and reversed every other time resulting in an increasing spiral pattern as shown below. The SEARCH2 pattern is as follows: SEARCH LIMIT SEARCH INCREMENT SEARCH2 can be initiated manually by selecting the SEARCH2 function under the MODE/CONTROL display and pressing the UP key. SEARCH2 is terminated automatically when the AGC level exceeds the threshold. Pressing AUX1 terminates SEARCH2. 3.5.3. SEARCH INCREMENT The size of the increase in the spiral pattern is set by the SEARCH INC parameter under the MODE/SETUP display. The units are in pedestal step resolution (1/24 degree for xx96 and xx97 systems and 1/6 degree for 9695 systems). The typical SEARCH INC setting is 1/2 the antenna 3 dB Beam Width. 3.5.4. SEARCH LIMIT The overall size of the search pattern is set by the SEARCH LIMIT parameter under the MODE/SETUP display. The units are in pedestal step resolution or 1/24 degree for xx96 and xx97 systems and 1/6 degree for 9695 systems. The typical SEARCH LIMIT setting is 2 to 4 degrees. 3.5.5. SEARCH DELAY SEARCH2 is initiated automatically if TRACKING is enabled and the AGC signal drops below the tracing threshold (THRS) for more than a preset time. The delay time is set by the SEARCH DELAY parameter under the MODE/SETUP display. The units are in seconds. The typical SEARCH DELAY setting is 30 seconds. A setting of 0 disables the automatic search initiation. 3.5.6. AUTO THRESHOLD SETTINGS When AUTO THRESHOLD is enabled, the DAC-97 automatically re- sets the AGC tracking threshold whenever the antenna is commanded to move to a new position by a numeric keyboard entry (SAT, EL, AZ commands). The new AGC threshold is set to the average signal level input (approximate background noise level) plus the AUTO THRES offset. The AUTO THRES parameter is adjusted under the MODE/SETUP display and should be set to approximately 1/3 the ON satellite to OFF satellite signal level difference. This will usually be around 100 counts (3 dB) for a typical antenna configuration. A setting of 0 disables the AUTO THRESHOLD feature. To quickly re- evaluate the tracking threshold with AUTO THRESHOLD enabled; move the antenna a few degrees up in elevation so there is no signal. Now key in the original elevation setting. This will force the DAC-97 to re-set the tracking threshold as it moves the antenna back to the satellite signal position. 3.5.7. STEP DELAY The speed of antenna movements during search operations is adjusted with the STEP DELAY parameter under the MODE/SETUP display. The STEP DELAY is the time the DAC-97 waits between sending incremental movement commands to the PCU. Larger numbers result in slower antenna movements through the search pattern. The units are in cycle updates of 1/40 second. The settings are 2 for xx96 and xx97 systems and 20 for 9695 systems. No other settings should be used. 3.6. AUTO POLARIZATION OPERATION (NOT USED BY MBARI) A feature of the DAC-97 is auto polarization adjustment. The DAC-97 automatically calculates the required polarization angle for the feed every 2 seconds based on ship's Latitude, Longitude and the Satellite Longitude. If the feed is not properly oriented, the DAC-97 will send a command to the PCU to adjust the feed. The system will function with 24V DC motor driven feeds, 5V servo drive probes and combination Linear / Circular (HCDC) feeds. The following section describes the alignment and operation of various feed types. 3.6.1. 24V DC POLANG ALIGNMENT 1. Select the POL TYPE parameter under the MODE/SETUP display and change the POL typesetting to 9 (8+1). Press ANTENNA key 3 times to select the POL display. Rotate the feed using the UP and DOWN keys so that the feed is in the CENTER of its range and the ports are aligned Horizontal and Vertical (Align the metal patches horizontally and vertically on an HCDC feed with the Ku band LNB at 2 o'clock). This is the Center Reference position. 2. Verify the POL display reads 120 +/-10. Adjust the potentiometer on the feed if necessary to bring this reading into spec (2.5v for xx96/xx97 systems). Note the display reading as the Center Reference value. 3. Rotate the feed CW 90 degrees viewed looking towards the satellite (CCW looking into the dish) by pressing the UP key. The display reading must have INCREASED. Record the change in the POL display reading from the Center Reference value. The change must be 60 or 90. If it is any other value, there is a problem with the polang potentiometer scale settings and should be corrected for proper operation. 4. Rotate the feed CCW 180 degrees or as far as it will travel, viewed looking towards the satellite (CW looking into the dish). If the feed allows full 180-degree rotation, the POL display will show 60 or 90 counts below the center reference value. Enter this value as the POL OFFSET parameter and the value recorded in step 3 as the POL SCALE parameter under the MODE/SETUP window. NOTE: If the feed does not allow a full 180 degree rotation to the CCW position, (CW looking into the dish), move the feed as far as it will go and readjust the polang potentiometer setting so the POL display shows 30-32. Move the feed to the center position and note the new reading. Calculate the POL OFFSET as the Center minus POLSCALE value and enter in the DAC-97 parameter list. 5. Align the feed for optimum polarization with the UP/DOWN keys and note the POL display. Select the POL TYPE parameter again and change the POL TYPE to 72 (64+8) to enable auto pol. If the POL position is not optimum using auto pol, trim the POL position up or down by adjusting the POL OFFSET parameter. 3.6.2. 5V SERVO POLANG ALIGNMENT 1. Select the POL TYPE parameter under the MODE/SETUP display and change the POL type setting to 48 (16+32). Press ANTENNA key 3 times to select the POL display. Rotate the feed probe using numeric entries in the range of 75 to 100 so that the probe is aligned with the horizontal metal patches in the feed. Note the POL display reading as the CCW value. 2. Rotate the probe CW 90 degrees and align with the vertical metal patches (use numeric entries around 180 to accomplish this). Note the POL display reading as the CENTER value. 3. Enter the CCW value in the 5V OFFSET parameter and the difference of CENTER-CCW value in the 5V SCALE parameter under the MODE/SETUP display. 4. Verify probe operation by setting the POL TYPE parameter to 4 then select the POL display in the ANTENNA window and cycle the NS/EW key. The probe should move from the horizontal alignment position to 45, 90 and 135 degrees clockwise then return. 5. For linear receive only feeds that do not have a 24 Volt DC Motor attached, enter the CCW and CENTER-CCW values in the POL OFFSET and POL SCALE parameters also. Select the POL TYPE parameter and change the POL TYPE to 112 (64+32+16) to enable auto pol with a numeric display. Select the POL display in the ANTENNA window. Use the NS/EW key to toggle receive polarity. If the POL position is not optimum using auto pol, trim the POL position up or down by adjusting the POL OFFSET parameter. Change the POL type to 80 (64+16) for normal operation. 3.6.3. LINEAR / CIRCULAR (HCDC) POLANG ALIGNMENT 1. Perform steps 1-4 of the 24V Polang Alignment. 2. Position the Ku Band LNB at 2 o'clock (facing the feed). Perform steps 1-4 of the 5V Servo Polang Alignment. 3 Select the POL TYPE parameter and change the POL TYPE to 68 (64+4), set the TX POLARITY to 0. Select the POL display in the ANTENNA window. Use the NS/EW key to change feed polarity (HORZ, LHCP, VERT, RHCP) as required. 4. Select POL TYPE 13 (8+4+1) to manually adjust and monitor POL position. Select POL TYPE 72 (64+8+4) to enable auto polarization. If the POL position is not optimum using auto pol, trim the POL position up or down by adjusting the POL OFFSET parameter. Change the POL TYPE to 68 (64+4) for normal operation. 3.6.4. TX POLARITY SETUP To prevent inadvertent switching of the transmit polarity, the user can lock out NS/EW toggle feature and force the transmit polarity to be fixed horizontal or vertical with the TX POLARITY parameter under the MODE/SETUP display. With the feed in the center of its polarization adjustment range, observe the transmit port polarity (vector across the short dimension of the transmit wave-guide). If the transmit polarity in the center of the travel range is vertical, use the following entries: 2 Vertical Transmit Polarity 4 Horizontal Transmit Polarity If the Transmit polarity in the center of the travel range is horizontal, use the following entries: 2 Horizontal Transmit Polarity 4 Vertical Transmit Polarity 3.7. RADIATION HAZZARD and BLOCKAGE MAPPING DAC-97 can be programmed with ship relative azimuth limits to enhance operation where there are radiation hazards or known blockage regions. Tracking and auto search are suspended when the antenna is pointed within this region to speed signal re-acquisition when the ship turns and the antenna comes out of signal blockage. The DAC-97 provides a contact closure to ground on the AUX SW terminal (J2-11) when the antenna is pointed within the blockage region to provide switching information to a multiple antenna arbitrator or to automatically suppress RF transmission to reduce radiation hazards. The contact closure is a transistor switch with a current sinking capability of 200 mA and is activated when the antenna is in the blockage region, or the system is searching, targeting or unwrapping. The lower and upper limits are user programmable and stored in NVRAM within the DAC-97 parameter list. Programming instructions: 1. Determine the Relative AZ limits that cause signal blockage or a radiation hazard by monitoring the REL display readings or by graphing the expected blockage pattern. The Relative angles are with respect to the Pedestal reference, which is normally pointed at the bow (360). In a dual cable-wrap antenna system, one of the antennas may be pointed aft so its relative limits will be with respect to aft. The relative angles must be in the range of 0 to 360 degrees. 2. Convert the relative readings to limit values by multiplying by 10. Enter the lower and upper limits (CW reference) in the DAC-97 by selecting the AZ LIMIT1 and AZ LIMIT2 parameters under the MODE display. If the MODE display will not advance beyond the REMOTE AUX display, enter 7979 and press ENTER. Enter the beginning of the blockage region as AZ LIMIT 1 and the end of the region (clockwise direction) as AZ LIMIT 2. EXAMPLE: A drill ship has two antennas mounted in the front of the ship with a derrick blocking the antenna's view to the rear. The Port antenna is mounted referenced to the bow and is blocked from 160 to 175 degrees. The Starboard antenna is mounted reference to the stern and is blocked from 355 to 15 degrees relative to the stern. The limits for the port antenna are: The limits for the starboard antenna are: AZ LIMIT 1 = 160 x 10 = 1600 AZ LIMIT 1 = 355 x 10 = 3550 AZ LIMIT 2 = 175 x 10 = 1750 AZ LIMIT 2 = 15 x 10 = 0150 Note: The AZ LIMITS of the starboard antenna are entered as 355 to 15 degrees. This defines a blockage zone of 20 degrees. If the limits were entered as 15 to 355 degrees, the blockage zone would be 340 degrees. 3.8. FUNCTION SUMMARY The following tables are a comprehensive summary of the information displayed in each of the four function modes. 3.8.1. SHIP DISPLAYS LAT Ships Latitude. Displayed in whole degrees. Can be entered to tenths of a degree. (36On) Used to calculate elevation and azimuth from satellite position. Can be updated [IN PORT] automatically with the addition of a NMEA interface. LON Ships Longitude. Displayed in whole degrees. Can be entered to tenths of a degree. (122Ow) Used to calculate elevation and azimuth from satellite position. Can be updated [IN PORT] automatically with the addition of a NMEA interface. HDG Ships Heading. Updated automatically from the gyro compass interface or (292.2o) pedestal Flux gate compass. Used for azimuth stabilization and to calculate [IN PORT] antenna position. 3.8.2. SATELLITE DISPLAYS SAT Satellite longitude. Displayed in whole degrees. Can be entered to tenths of a (121oW) degree. Used to calculate antenna elevation, azimuth and polang pointing angles. Tracking threshold is re-set and the antenna is moved automatically when entry is changed. THRS Signal level threshold. SEARCH2 is started automatically when signal is below (3100) threshold for SEARCH DELAY period. SEARCH1 and SEARCH2 are terminated automatically when signal level exceeds threshold. System type 16 disables tracking when the signal level is below threshold. RCVR Receiver tuning or selection. NS/EW Entry selects one of 4 AGC sources. Numeric (EXT RCVR) entry selects channel number or tuning frequency in MHz. AGC Signal AGC level. Diagnostic display of signal level. Range is 0-4095 for 0-5v (~3300) input. Cannot be selected for entry. 3.8.3. ANTENNA DISPLAYS AZ True azimuth position. Displayed in tenths of a degree. Display is sum of ships (152.2o) heading and antenna relative position reduced to 0-360 degrees. Position can be [IN PORT] incremented or decremented with UP/DOWN keys. Can be targeted to an absolute or relative position by numeric entry. NS/EW key selects relative target mode. Searching light flashes when targeting. Display can be corrected up or down with AZTRIM entry under MODE/SETUP display. EL Elevation position. Displayed in tenths of a degree. Position can be incremented (000.1o) and decremented with up/down keys. Can be targeted to an absolute position by numeric entry. Searching light flashes when targeting. Display can be corrected up or down with ELTRIM entry under MODE/SETUP display. REL Antenna position relative to the bow of the ship. Displayed to tenths of a degree. (585.2o) Range of display is 90-630, with 360 indicating antenna is pointed at the bow. Used to indicate when the antenna is near an unwrap point and if the antenna is pointing at any large structures on the ship. Diagnostic display only, cannot be selected for entry. POL Polang (Polarization Angle) Position. Appears in place of REL display in entry mode. (HORZ) NS/EW key selects HORZ, LHCP, VERT, RHCP preset or calculated probe/feed positions. UP/DOWN keys adjust Polarization angle clockwise or counter- clockwise for fine-tuning. Display is numeric value of polang position or ALPHA display of HORZ, LHCP, VERT, RHCP polarization. AGC Signal AGC level. Provided as a diagnostic display for manually peaking AZ, EL or (~3300) POL for best signal level. Cannot be selected for entry. 3.8.4. MODE DISPLAYS The mode displays are separated into 3 groups: CONTROL, STATUS and SETUP. Normally only the CONTROL and STATUS groups are available. To gain access to the SETUP displays, you must select the REMOTE AUXZ diagnostic display and press 7979 enter. This procedure only needs to be performed once to allow access to the SETUP displays unless power is removed or the TAC is reset. MODE CONTROL DISPLAYS TRACKING Used to turn tracking mode ON and OFF and select operating bands. UP key (ON) toggles tracking state. DOWN key toggles band from C to Ku. Tracking can be turned on and off directly via the AUX1 key without selecting the MODE/CONTROL/TRACKING display. SEARCH1 Used to manually turn the one axis azimuth search ON and OFF. Up/down keys (OFF) select searching state. SEARCH1 is automatically initiated when a new satellite longitude is entered and SEARCH1 priority is enabled. AGC above threshold automatically terminates SEARCH. AUX1 manually terminates SEARCH. SEARCH2 Used to manually turn two axis spiral search ON and OFF. Up/down keys select (OFF) search state. SEARCH2 is automatically initiated when signal drops below threshold for SEARCH DELAY time. AGC above threshold automatically terminates SEARCH. AUX1 manually terminates SEARCH. MODE STATUS DISPLAYS ERROR Display of serial communication error count and error status code. Pressing UP (0000) clears error count, status code and Error LED. Occasional communication error counts are normal. More than 10 per minute indicate a problem that needs attention. Error status code is the sum of the following errors. 128 Satellite out of range 16 Conscan disk sensor error 8 Pedestal function error 4 Remote serial error 2 Wrong Synchro Converter type 1 Gyro Read Error REMOTE AUX Diagnostic display of Remote auxiliary read. Typically used for Temperature (XXXX) or EIRP readings. Users are locked out of remaining displays unless access code 7979 is entered. MODE SETUP DISPLAYS ELTRIM Elevation trim offset. Adjusts display to correct for antenna alignment errors or (0000) imbalances in the antenna system. Increase number to increase display. AZTRIM Azimuth trim offset. Used to correct for Magnetic Variation when using internal (-0032) flux gate compass. Positive numbers indicate East Variation (Western US); Negative numbers indicate West Variation (Eastern US). Offsets true azimuth display to compensate for installation alignment when using external gyro reference. Does not affect REL azimuth reading. Increase number to increase display. AUTO THRES Sets offset of AGC tracking threshold above the average noise floor. Units are in (0000) A/D counts, approximately 30 counts/dB (default setting is 128). A setting of 0 disables auto threshold. ELSTEPSIZE Sets elevation step track trial steps or Conscan sensitivity. Units are in pedestal (0001) step resolution. Range is 0-255 steps. Zero steps disables elevation step track. Must be entered twice for Conscan settings. AZ STEP SIZE Sets azimuth step track trial steps or Conscan sensitivity. Units are in pedestal (0002) step resolution. Range is 1-255 steps. Must be entered twice for Conscan settings. STEP DELAY Inter-step delay for search movements. Controls how fast the antenna is moved by (0002) setting the number of cycle updates between antenna steps. Heavy antenna systems need larger delays (slower movements). Each cycle update is 1/40 second. Range is 2-255. SEARCH INC Sets size of search pattern increment. Units are in pedestal step resolution (1/24 (0024) degree for xx96/97). The suggested setting is equal to 1/2 the 3dB beamwidth. Range is 0-255 steps. SEARCH LIM Sets the overall peak to peak size of the search pattern. Units are in pedestal step (0200) resolution. Range is 0-255 steps. Default setting is 100 steps or 4.2 degrees. SEARCH DEL Sets the time-out for automatic initiation of a search operation when the signal (0000) level drops below threshold. Units are in seconds. Range is 0-255 seconds. A setting of 0 disables automatic search initiation. STEP INT Sets the integration time for each step track trial move. Units are in cycle updates (0040) (1/40 seconds). Range is 0-255 cycles. Recommended integration time is 1-5 seconds (40-200 cycles). A setting of 0 disables Step Track and enables Conscan SYSTEM TYPE Selects system options according to the following table. Add together all the (0024) desired options to determine the proper entry. 64 Enables LNB voltage output 2 Display Relative AZ during AZ entry 16* Disable Tracking below threshold 8* Enable NMEA / M&C interface 4 Auto SAT load at RESET and search failures 2 SEARCH1 priority for auto search 1 Reserved GYRO TYPE Selects the type of gyro compass interface for ship turning compensation. 0 (0002) indicates Internal Magnetic reference. 2 indicates S-B-S gyro interface. 1 to 360 indicates a 1:1, 36:1, 90:1 or 360:1 Synchro gyro interface. 362 indicates 360:1 synchro using 12bit S/D interface. THE FOLLOWING COMMANDS ARE NOT UTILIZED BY MBARI AT THIS TIME: POLANG TYPE Selects the Polang options installed according to the following table. Add (0000) together all the desired options to determine the proper POLANG TYPE entry. 128 Indicates 2 quadrant LHCP/RHCP display 64 Indicates Auto Pol Enabled 32 Indicates 5v numeric Polang display 16 Indicates 5v polang skew (not mode select) 8 Indicates remote potentiometer read 4 Indicates 4 quadrant HLVR presets 2 Reserved 1 Indicates 24v manual polang drive 0 Indicates alpha POLANG display (HORZ, LHCP.VERT, RHCP) POL OFFSET CCW 24V Polang pot position reference. (0000) POL SCALE 90 degree 24V Polang pot motion scale factor (0000) AZ LIMIT 1 Lower Relative AZ limit for pattern blockage mapping. (0000) AZ LIMIT 2 Upper Relative AZ limit for pattern blockage mapping (0000) TX Polarity Selects TX polarity override to disable NS/EW polang selection and coordinate TX (0000) polarities. 0 Indicates no TX polarity override 2 Indicates Vertical desired TX polarity 4 Indicates Horizontal desired TX polarity SAVE NEW PARAMETERS: Press UP arrow and ENTER to save any recent changes in NVRAM for permanent storage. If changes are made and not stored, they will still be effective but will be lost when power is removed or the DAC-97 is RESET. Press AUX2 and CLEAR simultaneously to access this function directly from any other mode. 3.8.5. REMOTE PCU CONTROL These commands are accessed under the MODE menu by pressing the ENTER key several times after the SAVE PARAMETERS display. REMOTE COMMAND Allows sending any arbitrary command to the PCU from the Command window. All checksums and response strings are handled by the DAC-97. Requires an understanding of the command set for the PCU being addressed. Key in ".nnn ENTER" where nnn is the ASCII value of the command character to send. The character will appear in the command window followed by 4 zeros. Key in the numeric command value and ENTER. The command will be sent to the PCU. PCU response will appear in the lower display. See Section 4 for details on specific uses of this function. REMOTE MONITOR Allows monitoring any status request from the PCU in the DAC-97 Monitor window. Select the REMOTE COMMAND window and key in ".nnn ENTER" where nnn is the ASCII value of the desired status request character. Select the REMOTE MONITOR window and the status request will be updated approximately 5 times per second. See Section 4 for details on specific uses of this function. REMOTE TILT Allows easy access to the tilt adjustment commands. Press UP arrow and ENTER to select TILT adjustment Test mode. Press 5 to center the tilt sensor adjustment. Press 4/6 to adjust the tilt left and right. Press 2/8 to adjust the tilt forward and back. Press DOWN arrow and ENTER to restore normal system operation. REMOTE PARAMETERS Allows easy access to the save remote parameters command sequence. Press UP arrow and ENTER to save the parameters in the remote PCU's NVRAM. 4. MAINTENANCE This section describes several adjustments to the system that can be accomplished by shipboard personnel. 4.1. PEDESTAL CONTROL UNIT CONFIGURATION The xx96/97 PCU is designed to be used with a variety of antenna pedestal configurations. The configuration information that is unique to each pedestal type is stored in a Non Volatile Random Access Memory (NVRAM) in the PCU enclosure. If the PCU is replaced or the NVRAM in the PCU should become corrupt, the PCU must be re-configured to operate with the pedestal it is installed on. The default configuration for the PCU is model xx97. In this configuration the PCU will not drive any of the three torque motors to prevent damage to the unknown pedestal. To configure the PCU, find the model configuration number from the pedestal manual or the table at the end of this section. Select the REMOTE COMMAND window on the DAC-97 by pressing the MODE key until this window appears (if the DAC-97 will not advance beyond the REMOTE AUX window, enter 7979 and press ENTER). In the REMOTE COMMAND window, key in ".78 ENTER". "N0000" should appear in the command window. Key in the pedestal configuration number, i.e. 131 for a 9697. Press ENTER to send this system type command to the PCU. Press ENTER several time to select REMOTE PARAMETERS. Press UP arrow and ENTER to save the system type in the PCU. Press ANTENNA, MODE, NS/EW to display the Remote Version Number. It should now display the correct model and version number. 4.2. DISPLAY OFFSET ADJUSTMENTS The displayed Elevation and Azimuth positions may be different than the calculated look angles due to mechanical installation or magnetic variation offsets. If the displays are consistently off by the same amount, you may correct the displayed positions by the following procedure. 1. Note the magnitude and direction of the errors in elevation and azimuth you wish to offset. Divide the error by 0.1 then add or subtract this value from the preset trim value. 2. Press the MODE key until the ELTRIM display is indicated. If the MODE will not advance beyond REMOTE AUX, press 7979 and ENTER. Adjust the ELTRIM display up or down by the amount calculated in step 1. Key in the new entry and press ENTER. For negative entries, press the NS/EW key. 3. Press the MODE key until the AZTRIM display is indicated. Adjust the AZTRIM display up or down by the amount calculated in step 1 or enter the magnetic variation x 10. Positive numbers indicate East Variation. For negative entries, press the NS/EW key. 4. Press the MODE key until the display indicates SAVE SETUP PARAMETERS. Press UP and ENTER. EXAMPLE: The Azimuth display consistently reads 3 degrees high. The AZTRIM value is set to 0 (default). To correct this error, the AZTRIM value needs to be "reduced" by 3 divided by 0.1 = 30 counts so the new AZTRIM value should be -30. 4.3. ANTENNA PEDESTAL OFFSET ADJUSTMENT Large variations in Azimuth position indicate the Azimuth Reference position is incorrect and should be corrected with a reference offset instead of an Azimuth Trim offset. This is especially true if sector blockage mapping is used. Pedestal software version 1.20 and later allows adjustment of the Azimuth Reference home flag to compensate for installation variations. To offset the Azimuth Reference home flag position, select the REMOTE COMMAND window on the DAC 97 by pressing the MODE key several times. In the REMOTE COMMAND window, key in ".78 ENTER". "N0000" should appear in the command window. Key in 6 and three digits for the azimuth reference offset value from 000 to 255 (corresponding to 0 to 360 degrees). Press ENTER to send the offset s system type command to the PCU. Press ENTER several time to select REMOTE PARAMETERS. Press UP arrow and ENTER to save the system type in the PCU. 4.4. ANTENNA POSITION ERROR MONITORING The DAC-97 provides a means for monitoring the position error of the antenna for diagnostic purposes. If this error is excessive, it indicates external forces are acting on the antenna. These forces may be the result of static imbalance, excessive bearing friction, cable binding, or wind loading. To view the position error, select the REMOTE COMMAND window on the DAC-97 by pressing the MODE key several times. Key in ".120 ENTER" (note the decimal point). "x0000" should appear in the command window. Press the MODE key once more to display the REMOTE MONITOR window. The lower display will show "iv" and three 4 digit hex numbers. The numbers indicate Cross Level, Level and Azimuth errors at a resolution of 1 part in 65536 or 0.0055 degrees. For example a display like "iv FFFF 0001 FFFD" indicates the Cross Level error is -.005 degrees, the Level error is + .005 degrees and the Azimuth error is -.016 degrees. The normal range of these numbers is FFF0 to 000F and they typically will bounce around randomly within this range. 4.5. OPEN LOOP SENSOR TEST The DAC-97 provides a means for monitoring the output of the 3 solid state rate sensors and the 3 reference sensors for diagnostic purposes. These sensors are the primary inputs to the PCU for stabilization. To monitor the rate sensors, select the REMOTE COMMAND window on the DAC-97 by pressing the MODE key several times. Key in ".119 ENTER" (note the decimal point). "w0000" should appear in the command window. Press the MODE key once more to display the REMOTE MONITOR window. The lower display will show "w" and three 4 digit decimal numbers. The numbers represent the Cross Level, Level and Azimuth rate sensor outputs respectively with a nominal display of 2048. The Cross-Level display should decrease when the antenna is tilted to the left and increase when tilted to the right. The Level display should decrease when the antenna is tilted forward and increase when tilted back. The Azimuth display should decrease when rotated CCW and increase when rotated CW. The display change occurs during movement and returns to nominal when movement stops. To monitor the reference sensors, select the REMOTE COMMAND window on the DAC-97. Key in ".118 ENTER" (note the decimal point). "v0000" should appear in the command window. Press the MODE key once more to display the REMOTE MONITOR window. The lower display will show "v" and three 4 digit decimal numbers. The numbers represent the Cross-Level and Level Tilt Sensor outputs and the azimuth home flag respectively. The nominal display is 2048 for the tilt sensors and either 0020 or 4050 for the home flag. The Cross Level Tilt display should decrease when the antenna is tilted to the left and increase when tilted to the right. The Level tilt display should decrease when the antenna is tilted forward and increase when tilted back. The Home Flag display will show 4050 when the home flag magnet is away from the sensor and 0000 when the home flag magnet is under the sensor. The display changes are static and remain displaced as long as the level platform is disturbed or the home flag sensor is activated. 4.6. OPEN LOOP MOTOR TEST The DAC-97 provides a means for driving each individual torque motor to test that motors functionality. By driving each axis and observing the resulting motion of the antenna, a coarse operational status of the motor and motor driver can be established. To manually drive the motors, select the REMOTE COMMAND window on the DAC-97. Key in ".94 ENTER" (note the decimal point). "^0000" should appear in the command window. To drive the Cross Level motor, key in 1064, 1128 or 1192 to drive the Cross Level axis left, off and right respectively. To drive the Level motor, key in 2064, 2128 or 2192 to drive the level axis forward, off or back. To drive the Azimuth motor, key in 3064, 3128 or 3192 to drive the azimuth axis CW, off or CCW. 4.7. DEFAULT SETUP PARAMETERS - xx96 xx97 The following table shows the factory default parameters for the DAC-97 interfaced to a 9697 style PCU: PARAMETER C BAND C Conscan Ku Conscan MBARI EL TRIM 0 0 0 0 AZ TRIM 0 0 0 -32 AUTO THRES 128 128 128 0 EL STEP SIZE 3 1 3 1 AZ STEP SIZE 3 1 3 2 STEP DELAY 2 2 2 2 SEARCH INC 10 10 5 24 SEARCH LIMIT 200 200 100 20 SEARCH DELAY 30 30 30 0 STEP INTEGRAL 60 0 0 40 SYSTEM TYPE 8 8 8 24 GYRO TYPE 1, 2, 36, 360, or 362 2 POL TYPE 9, 68 or 72 9, 68 or 72 9 or 72 0 POL OFFSET 60/30 60/30 30 0 POL SCALE 60/90 60/90 90 0 AZ LIMIT 1 0 0 0 0 AZ LIMIT 2 0 0 0 0 TX POLARITY 0/2 0/2 0/2 0 4.8. MODEL CONFIGURATION PARAMETERS The following table shows the current mode configuration values for xx96 and xx97 pedestals. MODEL Configuration Number 3796 N 0072 4096 (sz 23 DR AZ motor) N 0097 Set N 3035 also 4896 (sz 34 AZ motor) N 0073 4896 (sz 23 DR AZ motor) N 0105 Set N 3040 also 4996 (az 23 DR AZ motor) N 0106 Set N 3040 also 5696 (sz 34 AZ motor) N 0075 5696 (sz 23 DR AZ motor) N 0107 Set N 3040 also 8297 N 0131 8897 N 0132 9497 N 0133 9697 N 0130 12097 N 0134 14497 N 0135 xx97 N 0000 Turns off all drive motors 4.9. TROUBLE SHOOTING GUIDE. The following appendices will aid in diagnosing the most common problems found during installation or operation. Section 5 contains a complete set of schematic and assembly drawings to aid in diagnosing any type of failure. 4.9.1. DAC-97 DISPLAYS "REMOTE NOT RESPONDING" Either the RS422 communications link with the antenna has failed or the pedestal control unit has failed. For Conscan equipped systems observe if the disk sensor light on the Conscan PC Board is flashing. A flashing light indicates the communication from the PCU to the ACU is functioning. Verify the operation of the PCU if possible by using a handheld ASCII terminal connected to the interface cable at the pedestal multiplexer. Verify the RS422 signal levels and connections. Refer to drawing 116040 "Unlimited Azimuth Interconnect Diagram" at the end of this manual for details on the signal levels and their flow directions. Using a spectrum analyzer observe the 1.1 and 1.5 MHz Pedestal M&C carrier signals on the RX IF cable. Hold the DAC-97 RESET key down and observe the 1.5 MHz signal is at a steady high frequency of 1.525 MHz. Release the RESET key and the signal should occasionally be seen switching to 1.475 MHz. This indicates the Base Multiplexer is transmitting to the PCU. 4.9.2. HEADING DISPLAYS INCRORRECTLY Ships' heading on the ACU does not follow the ship movement or does not display the same heading as the bridge. Determine the type of gyrocompass that is used on the ship then proceed to the step that lists the correct type. 1) 1:1 SYNCHRO Note: The standard ACU is set up for either 360:1 or step-by- step. To operate with a 1:1 synchro compass requires a special order from the factory. Observe the ship's heading display on the ACU. Compare its movement with that of the ship. If it does not move at all go to step A. If it moves but in the wrong direction (even if it does not display the correct heading) go to step B. If it moves in the correct direction but does not display the correct heading go to step C. The gyrocompass connects to the Terminal Mounting Strip on TB7- R1, R2, S1, S2 and S3. A. The Ships Heading display does not change when the ship changes direction. Using a multimeter read between R1 and R2. It should read 115 VAC. If it does not then a fuse is blown at the gyro repeater or there is an open between the repeater and the ACU. Read between S1 and S2, S2 and S3 and finally S3 and S1. They should all read between 0 and 90 VAC. The voltage level will change as the ship turns. If one reading is very close to 0 volts wait until the ship has made a major change in heading and then check voltage again. If the reading is still very low there is a problem in the line between the gyro repeater and the ACU or a problem in the gyro repeater itself. B. The display changes in the direction opposite of the movement of the ship. Switch the secondary leads S1 and S2. Caution: there is 90 VAC between them! Verify that when the ship changes direction the display shows change in the same direction. If the direction is correct but the heading is incorrect go to step C. C The ship's heading display does not indicate the correct heading. If the display is off by 60, 180 or 300 degrees, this indicates that R1 and R2 are reversed. Reverse R1 and R2 and recheck the heading display. If the display is off by 120 or 240 degrees, this indicates that S1, S2 and S3 are in the right order but off by one place. Note their positions and carefully move the connections one position over (S1 to S2, S2 to S3, and S3 to S1). This action will offset the display by 120 degrees. Check if the display now reads correctly. If not move all three leads one more time in the same direction as last time. Verify that the ship's heading is correct. 2) STEP-BY-STEP A Verify that the GYRO TYPE setting in the MODE display is set to 2 for Step-By-Step operation. C. Observe the ERROR LED on the FRONT panel. IF it is illuminated, this indicates that an error was detected in the Step-By-Step input. Press RESET on the front panel. If the ERROR LED illuminates again, the problem is in the 4 connections to A, B, C and COMMON. Measure the voltage between COMMON and A, B, and C. Each reading should either be near zero or 35 to 70 volts. If all three are zero, check the repeater fuses. If some read negative and some read positive or if one reads an intermediate values the COMMON terminal is not properly connected. D. If the ship's heading display is different from the actual heading, select the HDG function in the SHIP display mode by pressing the SHIP key 4 times. Key in the correct ships heading using the numeric keys and press ENTER. Note the reading. After the ship has turned more than one degree, compare the new heading with the reading on the display, if it has moved in the opposite direction then A, B and C from the gyro compass are not wired correctly. To reverse the direction of the display, reverse connections A and B. Reset the ACU, put in the correct ship's heading and verify that the display reading follows the ship's heading. 3) 360:1 Synchro Observe the ship's heading display on the ACU. Compare its movement with that of the ship. If it does not move at all go to step A. If it moves but in the wrong direction (even if it does not display the correct heading) go to step B. If it moves in the correct direction but does not display the correct heading go to step C. The gyrocompass connects to the Terminal Mounting Strip on TB7- R1, R2, S1, S2 and S3. A. The Ships Heading display does not change when the ship changes direction. Using a multimeter read between R1 and R2. It should read 115 VAC. If it does not then a fuse is blown at the gyro repeater or there is an open between the repeater and the ACU. Read between S1 and S2, S2 and S3 and finally S3 and S1. They should all read between 0 and 90 VAC. The voltage level will change as the ship turns. If one reading is very close to 0 volts wait until the ship has made a major change in heading and then check voltage again. If the reading is still very low there is a problem in the line between the gyro repeater and the ACU or a problem in the gyro repeater itself. B. The display changes in the direction opposite of the movement of the ship. Switch the secondary leads S1 and S2. Caution: there is 90 VAC between them! Verify that when the ship changes direction the display shows change in the same direction. If the direction is correct but the heading is incorrect go to step C. C. If the ship's heading is different than the bridge, select the HDG function in the SHIP display mode by pressing the SHIP key 4 times. Key in the correct heading using the numeric keys and press ENTER. 5. DRAWINGS The drawings listed below are provided as part of this manual. Refer to the Pedestal wiring diagrams supplied with the system for details on the antenna wiring. To view the drawings listed below from Acrobat Reader, click on the bookmark index to the left. To return to this page, use the << key from within Acrobat Reader or the BACK key if you are viewing from a web browser. Drawing Title 113105 TAC-92M ACU General Assembly 113106 TAC-92M Chassis Wiring Diagram 112512 Front Panel Interconnect PCB Schematic 113275 ACU PCB Assembly TAC-92 112226 TAC-92 ACU PCB Schematic 114836 12 Bit S/D Converter PCB Assembly 114648 12 Bit S/D Converter PCB Schematic 113747 Aux Serial Port Adapter PCB Assembly 113744 Aux Serial Port Adapter PCB Schematic 113037 AGC Receiver Interface PCB Assembly 113036 AGC Receiver Interface PCB Schematic 112019 70 MHz SCPC Detector PCB Assembly 112018 70 MHz SCPC Detector PCB Schematic 116676 ACU Terminal Mounting Strip Assembly 116685 ACU Terminal Mounting Strip Schematic 112791 Interface Cable Diagram GPS to ACU 116298 Interface Cable Assembly ACU to MUX 116670 RS-232 Cable Assembly 110762 RS 232 Interconnect Cable Diagram 116040 Unlimited Azimuth Interconnect Diagram 114493 TAC-92/DAC-97 User Interface Description Feb 1999/Seatel JULY 1999/GEO Document. No. 116363-D-MBARIPL