DATASONICS CAP-6600 Chirp II Acoustic Profiling System

Transcription

1 DATASONICS CAP-6600 Chirp II Acoustic Profiling System System Manual September 1999 Datasonics, Inc Route 28A Cataumet, MA U.S.A. Tel: (01) Fax: (01)

2 ii DATASONICS System Manual September 1999

3 CAP-6600 Chirp II Acoustic Profiling System iii Notices Proprietary Information The information, descriptions, photos and illustrations in this manual are the property of Datasonics, Inc. Materials may not be reproduced or disseminated without the prior written consent of Datasonics. Warranty On standard catalog products, Seller warrants the products delivered under this contract to be free from defects in material and workmanship at the time of delivery to the F.O.B. point specified in the order, its liability under this warranty being limited to repairing or replacing, at Seller s option, items which are returned to it FREIGHT PREPAID within one (1) year from delivery to the Buyer and found to Seller s satisfaction, to have been so defective. Items shall be returned to the Buyer FREIGHT PREPAID. On services, Seller warrants that all work performed by the employees will be done in a workmanlike manner. Seller s liability under this warranty is limited to remedying at its expense any work found to Seller s satisfaction not so performed, provided however, Seller is notified of any claims within three (3) months from the date the work is performed. In no event shall Seller be liable for consequential damages. NO PRODUCT IS WARRANTED AS BEING FIT FOR A PARTICULAR PURPOSE AND THERE IS NO WARRANTY OF MERCHANTABILITY. This warranty applies only if: (i) the items are used solely under the operating conditions and in the manner recommended in Seller s instruction manual, specifications, or other literature; (ii) the items have not been missed or abused in any manner or repairs attempted thereon; (iii) written notice of the failure within the warranty period is forwarded to Seller and the directions for properly identifying items returned under warranty are followed; and (iv) with return notice authorizing Seller to examine and disassemble returned products to the extent Seller deems necessary to ascertain the cause of failure. The warranties stated herein are exclusive. THERE ARE NO OTHER WARRANTIES, EITHER EXPRESSED OR IMPLIED, BEYOND THOSE SET FORTH HEREIN, and Seller does not assume any other obligation or liability in connection with the sale or use of said products. Any product or service repaired or replaced under this warranty shall be warranted for the unexpired portion of the original warranty period only. Notices

4 iv DATASONICS Liability Datasonics assumes no liability for damages, losses or costs incurred consequentially through operation or malfunction of Datasonics products. Title Title shall pass to the Buyer on delivery to the carrier at Cataumet, Massachusetts, U.S.A. Risk of damage or loss following such delivery shall be the Buyer's, and Datasonics shall in no way be responsible for safe arrival of the shipment. Title shall so pass to the Buyer regardless of any provision for payment of freight or insurance by Datasonics, and regardless of the form of the shipping documents. If shipment is consigned to Datasonics, it shall be for the purpose of securing the Buyer's obligations under contract. Changes Datasonics reserves the right to make changes in design or specifications at any time without incurring any obligation to modify previously installed units. This manual is provided for informational and reference purpose only and is subject to change without notice. System Manual September 1999

5 CAP-6600 Chirp II Acoustic Profiling System v Quick-Start/Reference Guide Use this Quick-Start/Reference Guide to quickly set up, activate and deploy the CAP-6600 Chirp II Acoustic Profiling System without having to read this entire manual. The Quick-Start/Reference guide also serves as a reference to those sections of the manual that describe in detail the steps required to perform these functions. Step 1: System Setup (Ref: Page 3-3) 1. Unpack the CAP-6600 Chirp II Workstation and the TTV-170, TTV-190 or TTV-173 Tow Vehicle. 2. Position and secure the workstation in place. 3. Assemble the tow vehicle. 4. Connect all the devices and the tow vehicle to the workstation: Connect the keyboard and the trackball to the KEYBOARD and MOUSE connectors on the front panel of the DSP-661 Processor. Connect the monitor to the VGA OUT connector on the rear panel of the processor. Connect the printer (optional) to the PRINTER connector. If applicable, connect the Remote Controlled Transmit/Receive Module in a hull mount system to the LPT2 connector. If applicable, connect the shipboard navigation system output to the NAV connector. Connect the SCSI storage devices (optional) to the SCSI connector. Connect the monitor AC power cable to the AC OUT connector. Connect an AC power cable to the VAC IN connector and to AC power. Connect an AC power cable to the VAC IN connector on the rear panel of the DSP-662 Transceiver and to AC power. Connect the 50-meter Kevlar reinforced deck 10-pin male Amphenol connector to the TRANSDUCER connector. Connect the opposite end of the deck cable to the tow vehicle. Quick-Start/Reference Guide

6 vi DATASONICS Step 2: System Startup (Ref: Page 3-19) 1. Start the DSP-661 Processor Software: Turn on all optional external devices. Turn on the monitor Turn on the DSP-661 Processor. Double-click the Chirp2 icon ( ) to open the Main and Chirp 2 Controls windows. 2. If a shipboard navigation system is connected, configure the navigation parameters: Select File from the menu bar, select Comm Ports, and then choose Comm Port Setup to open the Communication Port Setup dialog box. In the Setup area of the Communication Port Setup dialog box, select COM1. In the Baud Rate area select In the Data Bits area select 8. In the Stop Bits area select 1. In the Parity area select NONE. In the Nav Port area select COM1. In the Aux Port area select COM1. Check the Nav ON check box. Clear the Display Degrees check box. In the External Comments Template area check the Warning Sound for incoming Comment check box. Click OK. 3. Configure the recording parameters: Select File from the menu bar, and then choose Record to open the Record Setup dialog box. Click Display Only to open the Recording Data Rate dialog box. In the Recording Data Rate dialog box, check the User Define check box. System Manual September 1999

7 CAP-6600 Chirp II Acoustic Profiling System vii In the User Define Data Rate area of the Recording Data Rate dialog box, select Click OK. Click OK to "Warning: data will not be saved." Click Yes or No, as applicable, to "Is the navigation available now?" Select File from the menu bar, and then choose Stop. 4. Configure the display parameters: Select Window from the menu bar, select Default Setup, and then choose Basic Setup. Select Display from the menu bar, and then choose Display Gain. Click anywhere in the Profile - CH1+CH2 window. In the Current Gain area of the Display Gain Setup window, select Non-Linear, 22 db. In the Display Threshold area set CH 1 and CH 2 to 4. Click OK. 5. Activate the DSP-662 Transceiver: Turn on the transceiver. Set the CH 1 ANALOG IN, CH 2 ANALOG IN and DELAY KEY IN switches on the transceiver to OFF. Set the CH 1 and CH 2 HYDROPHONE switches to HYDROPHONE. In the Trigger Source area of the Chirp 2 Controls window, select Internal. Set the Trig Rate to s. In the Hardware Gain area set Ch1 and Ch2 to 0 db. In the Power Controls area set Ch1 and Ch2 to 0 db. In the Chirp Length area set Ch1 and Ch2 to 5 ms. Click SET. In the Track Channel area select CH 1. Select Auto. Quick-Start/Reference Guide

8 viii DATASONICS Set Track Sensitivity to 45%. Set Holdoff to 2 m. Set TVG Ch 1 and Ch 2 to Set Smooth to 0%. 6. Perform the predeployment checks: Select Tools from the menu bar, select Diagnose, and then choose System Diagnose to start the Chirp pattern test. Examine the profile displays in the Profile - CH1+CH2 window. After several minutes the displays should look similar to those shown in Figure 3-15 on page 3-28 with black and gray horizontal bars of gradually increasing intensity. To stop the system diagnostics, again select Tools from the menu bar, select Diagnose, and then choose System Diagnose. Turn off the Channel 1 transmitter by setting Ch1 in the Power Controls area of the Chirp 2 Controls window to OFF. Listen for the transmitted pulses from the high frequency transducer in the tow vehicle, and then turn the Channel 1 transmitter back on by setting Ch1 back to 0 db. Turn off the Channel 2 transmitter by setting Ch2 in the Power Controls area of the Chirp 2 Controls window to OFF. Listen for the transmitted pulses from the low frequency transducer in the tow vehicle, and then turn the Channel 2 transmitter back on by setting Ch2 back to 0 db. With a wrench or similar blunt object, rapidly tap the underside of the tow vehicle for 15 to 20 seconds in the area of the hydrophone arrays. Examine the profile displays in the Profile - CH1+CH2 window. The displays should look similar to those shown in Figure 3-17 on page 3-30 with vertical streaks displayed in both the CH 1 and CH 2 profile displays. If the vertical streaks cannot be seen, temporarily increase the Ch1 and Ch2 settings in the Hardware Gain area of the Chirp 2 Controls window. Also increase the Ch 1 and Ch 2 TVG settings in the Bottom Tracking-TVG section of the Chirp 2 Controls window. If navigation data are available, examine the Navigation-Status area of the Chirp 2 Controls window. Navigation data should be present. System Manual September 1999

9 CAP-6600 Chirp II Acoustic Profiling System ix Step 3: Tow Vehicle Deployment (Ref: Page 3-31) 1. Connect the armored multi-conductor tow cable if used: Turn off the DSP-662 Transceiver. Disconnect the 50-meter Kevlar reinforced deck cable from the tow vehicle and from the transceiver. Connect, but do not yet attach, the armored multi-conductor tow cable to the tow vehicle and connect the winch s deck cable to the processor. Turn the transceiver back on and repeat the predeployment checks in Step 2, System Startup (recommended). Attach the armored multi-conductor tow cable to the middle hole on the tow point on the tow vehicle. Hoist the tow vehicle, check for proper balance and, if necessary, reattach the armored multi-conductor tow cable to a different hole on the tow point. 2. Launch the tow vehicle: Lower the tow vehicle into the water using a boom or an A-frame and a winch. Submerge the tow vehicle to a depth of two or three meters, and then begin cruising at two to four knots. Select File from the menu bar, and then choose Record to open the Record Setup dialog box. Click Display Only to open the Recording Data Rate dialog box. Click OK. Should the Chirp 2 Navigation Warning dialog box open, signifying that navigation data are not available or the shipboard navigation system is not connected, click OK to close the dialog box. Verify operation by examining the profile displays in the Profile - CH1+CH2 window. Quick-Start/Reference Guide

10 x DATASONICS Preface Congratulations on your purchase of the CAP-6600 Chirp II Acoustic Profiling System! The CAP-6600 delivers high resolution subbottom profiling using advanced Chirp technology. This manual is divided into seven sections and two appendices: Section 1 - Overview describes the major system components and explains Chirp sonar technology. Section 2 - Specifications lists the specifications for the shipboard component of the system, the available tow vehicles, and a hull mount system. Section 3 - Setup and Deployment covers the unpacking and setup of the hardware, configuration of system parameters and a system startup procedure that includes predeployment checks and tow vehicle deployment. Section 4 - Operation provides a description of the control and recording parameter settings and includes some basic system operating instructions as well as a procedure for formatting a magneto-optical disk and recording data. Section 5 - Theory of Operation describes the circuit functions and signal flows at both the functional level and the circuit board level for the shipboard component of the system. Section 6 - Maintenance covers routine maintenance and includes troubleshooting guides and recommended test equipment and test procedures. Section 7 - Drawings includes the block diagrams, schematics, wiring diagrams and assembly drawings for the shipboard component of the system, and the wiring diagrams for the transducer and hydrophone cables in the available tow vehicles. Appendix A - Reloading the DSP-661 Processor Software provides two procedures for reloading the DSP-661 Processor Software: a System Restore and a System Setup. Appendix B - Hull Mount Installation Requirements includes a general overview of the requirements for installing a hull mount system. System Manual September 1999

11 CAP-6600 Chirp II Acoustic Profiling System xi Notes and Warnings Where applicable, special notes and warnings are presented as follows: NOTE A referral to another part of this manual or to another reference; a recommendation to check that certain criteria are met before proceeding further in a step or sequence; or general information applicable to the setup and operation of the CAP-6600 Chirp II Acoustic Profiling System. WARNING A reminder that dangerous or damaging consequences could result if certain recommended procedures are not followed. Comments We welcome your comments and suggestions for improving this documentation set, identifying specific applications for the CAP-6600 Chirp II Acoustic Profiling System and other Datasonics products, and developing better ways of serving you with acoustic technology. Please contact us at: DATASONICS, INC. Attention: Customer Service 1400 Route 28A Cataumet, MA U.S.A. Telephone: (01) Fax: (01) sales@datasonics.com Preface

12 xii DATASONICS Contents Notices iii Proprietary Information iii Warranty iii Liability iv Title iv Changes iv Quick-Start/Reference Guide v Preface x Notes and Warnings xi Comments xi Contents xii List of Figures xvii List of Tables xix SECTION 1 CAP-6600 Overview Main System Components Advantages of Chirp Sonar CAP-6600 Chirp II Workstation DSP-661 Processor DSP-661 Processor Software Data Fusion and Storage Realtime Display and Image Processing Post-Processing of Data DSP-662 Transceiver Tow Vehicles TTV-170 Tow Vehicle TTV-190 Tow Vehicle TTV-173 Tow Vehicle Hull Mount Transducer Array Chirp Technology Image Resolution Chirp Pulse Transmission and Reception System Manual September 1999

13 CAP-6600 Chirp II Acoustic Profiling System xiii SECTION 2 Specifications CAP-6600 Chirp II Workstation Physical Characteristics Software Computer Display Power Requirements Input/Output TTV-170 Tow Vehicle Physical Characteristics Low Frequency Sonar High Frequency Sonar Sonar Receiver TTV-190 Tow Vehicle Physical Characteristics Low Frequency Sonar High Frequency Sonar Sonar Receiver TTV-173 Tow Vehicle Physical Characteristics Sonar Sonar Receiver Hull Mount System Low Frequency Sonar High Frequency Sonar Remote Controlled Transmit/Receive Module SECTION 3 Setup and Deployment Unpacking Workstation Setup TTV-190 Tow Vehicle Assembly Workstation Hardware Connections Processor Front and Rear Panel Connections Transceiver Front and Rear Panel Connections Connecting the Workstation Connecting the Tow Vehicle Contents

14 xiv DATASONICS Workstation Operator Functions Processor Operator Functions Transceiver Operator Functions System Startup Activating the DSP-661 Processor Configuring the Setup Parameters Configuring the Navigation Parameters Configuring the Recording Parameters Configuring the Display Parameters Activating the DSP-662 Transceiver Performing the Predeployment Checks Tow Vehicle Deployment Selecting a Tow Cable Connecting the Tow Cable Launching the Tow Vehicle Other System Configurations Connecting an SPR-1200 Seismic Profiling System ("Bubble Pulser") Connecting an Alternate Seismic Source Setting Up the Channel 1 Bandpass Filter Setting Up the Channel 2 Bandpass Filter Connecting a Heave Compensator SECTION 4 Operation Control Settings Transmit and Receive Trigger Source Transmit Repetition Rate Chirp Pulse Length Receiver Gain Transmitter Power Display Gain and Threshold Bottom Tracking and TVG Recording Parameter Settings Recording Data Rate Recording File Format Recording Time Calculations Formatting a Magneto-Optical Disk Recording Data System Manual September 1999

15 CAP-6600 Chirp II Acoustic Profiling System xv SECTION 5 Theory of Operation Functional Description Processor Transceiver Circuit Board Description Processor Circuit Boards DSP Board Burst/Receiver Board Transceiver Circuit Boards Front Panel Distribution Board Rear Panel Distribution Board Power Amplifier Board Transformer Jumper Board SECTION 6 Maintenance and Troubleshooting Workstation Periodic Maintenance Air Filter Removal and Cleaning Backups Hard Disk Maintenance Utilities Tow Vehicle Periodic Maintenance Cleaning and Inspection System Troubleshooting Field Test Equipment Workstation Disassembly and Reassembly Troubleshooting Guides Cable Checks Arcing Continuity Short Circuit Test Transducer Checks Arcing Tap Test Short Circuit Test Transmit Test Changing the Transformer Jumpers Contents

16 xvi DATASONICS SECTION 7 Drawings Workstation Drawings Tow Vehicle Drawings Hull Mount System Drawings APPENDIX A Reloading the DSP-661 Processor Software A-1 Performing the System Restore A-3 Performing the System Setup A-4 APPENDIX B Hull Mount System Installation Requirements B-1 Transducer Array Configurations B-4 Transducer Location B-4 Transducer Installation B-5 System Wiring B-5 Junction Box B-6 Remote Controlled Transmit/Receive Module B-6 Workstation B-6 System Manual September 1999

17 CAP-6600 Chirp II Acoustic Profiling System xvii List of Figures Figure 1-1 CAP-6600 Chirp II Acoustic Profiling System Workstation Figure 1-2 TTV-170 Tow Vehicle for Shallow Water Applications Figure 1-3 TTV-190 Tow Vehicle for Deep Water Applications Figure 1-4 TTV-173 Tow Vehicle for Pipe Line Surveys Figure 1-5 Figure 1-6 Hull Mount Array with AT-471 and AT-12D7 Transducers CAP-6600 Chirp II Acoustic Profiling System Block Diagram Figure 1-7 Resolving Closely Spaced Layers Figure 3-1 CAP-6600 Chirp II Workstation Recommended Setup Figure 3-2 Assembling the TTV-190 Tow Vehicle Tail Fins Figure 3-3 DSP-661 Processor and DSP-662 Transceiver Front Panels Figure 3-4 DSP-661 Processor and DSP-662 Transceiver Rear Panels Figure 3-5 TTV-170 or TTV-190 Tow Vehicle Cable Connection Figure 3-6 TTV-173 Tow Vehicle Cable Connection Figure 3-7 The Main and Chirp 2 Controls Windows Figure 3-8 The Communication Port Setup Dialog Box Figure 3-9 The Record Setup Dialog Box Figure 3-10 The Recording Data Rate Dialog Box Figure 3-11 The Default Display Setup Figure 3-12 The Display Gain Setup Window Figure 3-13 DSP-662 Transceiver Default Switch Settings Figure 3-14 The Chirp 2 Controls Window Figure 3-15 The Chirp Pattern Test Display Figure 3-16 Location of TTV-190 Transducers and Hydrophone Array List of Figures

18 xviii DATASONICS Figure 3-17 The Tap Test Display Figure 3-18 Example CAP-6600 Chirp II Sonar Images Figure 3-19 The Bandpass Filter Setup Dialog Box Figure 4-1 The Format - Removable Disk Dialog Box Figure 4-2 The Format Results - Removable Disk Dialog Box Figure 4-3 The Record/Playback Dialog Box Figure 4-4 The Save As Dialog Box Figure 5-1 Transceiver Chassis Figure 6-1 Location of the Transformer Jumper Boards Figure B-1 Major Components of a Typical Hull Mount System.... B-3 Figure B-2 Inside-Hull Transducer Array Configuration B-4 System Manual September 1999

19 CAP-6600 Chirp II Acoustic Profiling System xix List of Tables Table 3-1 Tow Speed vs. Depth Table 3-2 Tow Speed vs. Cable Length Table 4-1 Transmit Repetition Rate vs. Maximum Tow Vehicle Altitude Table 4-2 Recommended Recording Data Rate Table 6-1 Processor Activation Problems Table 6-2 Transceiver Activation Problems Table 6-3 Predeployment Checks Problems List of Tables

20 xx DATASONICS System Manual September 1999

21 CAP-6600 Chirp II Acoustic Profiling System 1-1 SECTION 1 CAP-6600 Overview SECTION 1 CAP-6600 Overview

22 1-2 DATASONICS System Manual September 1999

23 CAP-6600 Chirp II Acoustic Profiling System 1-3 T he Datasonics CAP-6600 Chirp II Acoustic Profiling System is a fully integrated dual channel, dual frequency sonar system. The system uses advanced Chirp technology to produce high resolution subbottom profiles of both the shallow and deep subbottom layers. The system is modular in design as it can be configured with a variety of tow vehicles as well as hull mounted transducer arrays. In addition, the system will process and display data from a non-chirp source, such as the Datasonics SPR-1200 Seismic Profiling System, in one channel while simultaneously processing data from the Chirp source in the second channel. The system comprises the Datasonics CAP Chirp II Workstation shown in Figure 1-1 and a selection of tow vehicles including the TTV-170 shown in Figure 1-2, the TTV-190 shown in Figure 1-3 and the TTV-173 shown in Figure 1-4. A hull mount transducer array with AT-471 low frequency transducers and an AT-12D7 high frequency transducer also is available and is shown in Figure 1-5. The tow vehicles and the hull mount transducer array are each designed for specific applications; hence together they serve a broad range of applications. This section provides a general description of the system and its various configurations and identifies some of its important features. A review of chirp technology also is presented and how the system makes use of its important advantages. Main System Components The CAP Chirp II Workstation is the shipboard component of the system and includes the following: The Datasonics DSP-661 Processor that generates the Chirp waveforms, processes and displays the subbottom sonar data and monitors and controls system performance; The Datasonics DSP-661 Processor Software for Windows with matched-filter digital signal processing that generates multiple views of the sonar data as the information is collected and recorded on high-density storage media; and The Datasonics DSP-662 Transceiver, a dual channel, high power transmitter and receiver that drives the tow vehicle transducers or hull mounted transducer array and receives the subbottom echoes. SECTION 1 CAP-6600 Overview Main System Components

24 1-4 DATASONICS Figure 1-1 CAP-6600 Chirp II Acoustic Profiling System Workstation Figure 1-2 TTV-170 Tow Vehicle for Shallow Water Applications System Manual September 1999

25 CAP-6600 Chirp II Acoustic Profiling System 1-5 Figure 1-3 TTV-190 Tow Vehicle for Deep Water Applications Figure 1-4 TTV-173 Tow Vehicle for Pipe Line Surveys Figure 1-5 Hull Mount Array with AT-471 and AT-12D7 Transducers SECTION 1 CAP-6600 Overview Main System Components

26 1-6 DATASONICS The Datasonics tow vehicles are the subsea components of the system and are each individually designed to meet specific applications including the following: For shallow water surveys the TTV-170 Tow Vehicle includes a single low frequency transducer, a multiple element high frequency transducer and two hydrophone arrays arranged in a dipole configuration for a narrow receive beam in a compact, aluminum and fiberglass body; For deep water surveys the TTV-190 Tow Vehicle is configured with four low frequency transducers, one multiple element high frequency transducer, and a linear hydrophone array consisting of eight transducer elements; and For pipe line surveys the TTV-173 provides transmit and receive beam patterns specifically designed for detecting buried pipes. A hull mount transducer array allows deep water surveys to be performed without the use of a tow vehicle. A complete hull mount system includes the following: Multiple Datasonics AT-471 low frequency transducers that are installed in a hull-mounted sea chest and provide narrow low frequency transmit and receive beams; A Datasonics At-12D7 High Frequency Transducer that is installed with the low frequency transducers and contains multiple internal elements that provide narrow high frequency transmit and receive beams; and A Remote Controlled Transmit/Receive Module that connects the transducer arrays to the workstation and includes a transmit/receive (T/R) network and programmable gain amplifiers, which optimize performance in shallow water as well as in deep water; and All required cables and a junction box for installation and wiring of the hull mount transducer array. A system block diagram, which depicts the functional relationships of the shipboard processing electronics and the tow vehicle or hull mount transducer arrays and hydrophones, is shown in Figure 1-6. The block diagram also depicts the interface with the optional bubble pulser, which is the Datasonics SPR-1200 Seismic Profiling System. System Manual September 1999

27 CAP-6600 Chirp II Acoustic Profiling System 1-7 Figure 1-6 CAP-6600 Chirp II Acoustic Profiling System Block Diagram Advantages of Chirp Sonar Chirp sonar technology employs swept FM transmitted signals along with digital signal processing for matched-filter processing of reflected energy. The chirp technology delivers the following performance features: A greater dynamic range is attained as long FM pulses provide an additional 20 db to 30 db of dynamic range over conventional subbottom sonar systems; Enhanced resolution is achieved with matched-filter processing, as compared to systems using standard processing in the same frequency band, by correlating the return signals with a replica of the outgoing pulse; Transmitted waveforms are repeatable from pulse to pulse; The temporal resolution is constant, both with range and penetration; SECTION 1 CAP-6600 Overview Advantages of Chirp Sonar

28 1-8 DATASONICS The pulse characteristics are programmable, as the pulse length, span of frequency sweep and phase/amplitude calibration of the transmitted waveform can be varied without hardware changes; and The sonar data can be stored for off-line processing in SEG-Y format on a hard drive, a magneto-optical drive or other high-density storage devices. CAP-6600 Chirp II Workstation The CAP-6600 Chirp II Workstation comprises the DSP-661 Processor, the DSP-661 Processor Software and the DSP-662 Transceiver. Together the processor, the software and the transceiver serve to process, to display and to store both channels of subbottom sonar data. The CAP-6600 Chirp II Workstation also inputs and stores navigation data from the ship s navigation system and can output data, including the navigation data, through a variety of user-configurable outputs. In addition, the processor provides remote programmable receiver gain control of the Remote Controlled Transmit/ Receive Module. DSP-661 Processor The DSP-661 Processor, which runs the Datasonics, Windows based DSP-661 Processor Software, serves as the operator interface for monitoring and controlling the system and displaying the sonar data. The processor includes, in addition to its Pentium based processor and Windows 32-bit operating system, the following additional components: 1280 X 1024 high resolution color monitor Digital signal processors (2) Graphics processor Hard drive with a SCSI interface Magneto-optical drive (optional) CD ROM drive 1.44 megabyte floppy drive Keyboard Trackball System Manual September 1999

29 CAP-6600 Chirp II Acoustic Profiling System 1-9 The processor displays both channels of subbottom sonar data, each in their own separate Profile window. Other windows include Bathymetry, Signal Stacking and Voltage Signal one each for each channel. Any number of windows can be displayed simultaneously and in any combination. As the sonar data are received, the processor processes the data using matched-filter digital signal processing, applying continuous Short Time Fourier Transforms (STFT) for each sweep or transmit cycle. In addition, the full dynamic range of the processed data is recorded on digital storage media while being displayed on a high resolution, 1280 X 1024 or higher monitor. An optional digital thermal graphic recorder can be connected to print either the data currently being recorded or previously recorded data. DSP-661 Processor Software The DSP-661 Processor Software has enabled the development of compact, low cost, modular shipboard data acquisition and image processing systems such as the CAP-6600 Chirp II Acoustic Profiling System. The software supports the acquisition, processing and storage of two channels of subbottom sonar data as well as navigation data. And as the software runs under Windows, it allows independent control of the processing while the sonar records are stored on a hard drive, a magneto-optical drive or other high-density storage devices in SEG-Y format. SEG-Y is the standard format developed by the Society of Exploration Geophysicists for the storage of seismic data. Data Fusion and Storage While subbottom data are acquired and processed, other types of data can be input to the system through the processor s serial ports. For example, a navigation system can be connected. The navigation data are combined with the sonar data and merged into the standard data format in the processor before being displayed and recorded on high-density storage media. Although the data can be saved to the processor s hard drive, the higher density magneto-optical disk is more appropriate for storing the large files that are generated by the CAP-6600 Chirp II Acoustic Profiling System. SECTION 1 CAP-6600 Overview CAP-6600 Chirp II Workstation

30 1-10 DATASONICS Realtime Display and Image Processing The DSP-661 Processor Software runs under Windows, which facilitates a standard and familiar user interface. Windows also allows independent control of an unlimited number of data display windows, where several different types of data display windows are available, each suited to a specific data type, and where all are displayed on a 1280 X 1024 or higher monitor in 256 colors. Windows also allows multiple applications of the software to be run simultaneously. This enables the viewing of a previously collected file while collecting data in a new file. The DSP-661 Processor Software image processing features are a major advantage over simple sonar video displays. These tools greatly enhance the power of the processor and the capabilities for manipulating and interpreting data. Post-Processing of Data The DSP-661 Processor Software enables both a record mode for data acquisition and real-time image processing, and a playback mode for image processing and data analysis after the sonar records have been collected and processed. All the real-time image processing tools available with operation in record mode are also available in playback mode. DSP-662 Transceiver The DSP-661 Transceiver incorporates two power amplifiers as well as filtering for separating the received signals. The Chirp waveforms are input to the transceiver from the processor and are amplified by the power amplifiers which drive the transducers. Received signals are input to the transceiver, filtered and then output to the processor. The transceiver also includes a preamplifier with adjustable gain for amplifying the output of non-chirp systems such as the Datasonics SPR-1200 Seismic Profiling system, and two T/R networks, which allow the transceiver to transmit and receive from the same transducer or transducer array. System Manual September 1999

31 CAP-6600 Chirp II Acoustic Profiling System 1-11 Tow Vehicles The TTV-170, TTV-190, and TTV-173 tow vehicles are available for use with the CAP-6600 Chirp II Acoustic Profiling System. On small vessels the TTV-173 can also be used in an over-the-side configuration. Each tow vehicle is designed to function optimally in specific applications, yet each tow vehicle will function with the CAP-6600 Chirp II Acoustic Profiling System to acquire high resolution subbottom imagery using Chirp technology. In all the tow vehicles the low frequency transducers operate in the 2 khz to 7 khz band (Channel 1) and the high frequency transducers operate in the 8 khz to 23 khz band (Channel 2). TTV-170 Tow Vehicle The TTV-170 Tow Vehicle is designed for use on small boats in relatively shallow water; it will operate in depths of up to 600 meters. The tow vehicle is relatively small, with a length of 38.0 inches and maximum diameter of 18.0 inches, and is constructed of a two-part fiberglass shell and aluminum tow body. Installed in the vehicle are an AT-471 low frequency transducer, an AT-14F7C high frequency seven-element transducer and two 8-element hydrophone arrays. The hydrophone arrays are positioned in parallel, thus forming a dipole configuration that provides a narrower beam in the athwart direction. The transducers and hydrophones are interconnected with a block mold assembly that connects with a single connector pigtail. The tow vehicle can also be configured with a single AT-471 or AT-14F7C transducer for single frequency operation. TTV-190 Tow Vehicle The TTV-190 Tow Vehicle is designed to operate in depths up to 1000 meters. The tow vehicle is 64.0 inches long and 18.0 inches in diameter. It is constructed of two aluminum-reinforced fiberglass shells which are joined around the center of the vehicle. A tail fin assembly provides stability while the vehicle is under tow, and a bar with five through holes extends through the top of the vehicle to provide a selection of tow points. Four handles, two on each side, are installed for carrying the vehicle. The tow vehicle includes a transducer array consisting of four AT-471 low frequency transducers, an AT-14F7C high frequency seven-element transducer and an eight-element hydrophone array. The transducers and hydrophones are interconnected with a block mold assembly that connects with a single connector pigtail. SECTION 1 CAP-6600 Overview Tow Vehicles

32 1-12 DATASONICS TTV-173 Tow Vehicle The TTV-173 Tow Vehicle is designed to be used for pipe line surveys as the vehicle s combined transmit and receive beam pattern is relatively wide forward and aft and very narrow athwart. The tow vehicle is 24.0 inches long and 30.5 inches wide and includes an array of five AT-14E2 transducers and an AT-473D hydrophone array. The vehicle also includes a collar for over-the-side mounting. Hull Mount Transducer Array The Datasonics hull mount transducer array is configured in a hull-mounted sea chest and is permanently connected to the workstation. The system is designed primarily for deep water applications; however, the Remote Controlled Transmit/Receive Module, which is controlled by the workstation, allows for shallow water applications as well, as it is configured with two remotely controlled gain stages that amplify weak return signals and attenuate strong return signals. The hull mounted systems incorporate from 4 to 16 AT-471 low frequency transducers, which operate in the 2 khz to 7 khz band, and an AT-12D7 multiple-element high frequency transducer that operates in the 8 khz to 23 khz band. The transducers are wired through a junction box that connects to the Remote Controlled Transmit/Receive Module and the workstation. The hull mount systems do not use a separate hydrophone as the transducers perform both the transmit and receive functions through a T/R network in the module. Chirp Technology Chirp technology uses digitally produced linear FM acoustic transmissions to produce high resolution images of seafloor contours and subbottom layers. In all sonar systems, higher frequency content is invariably associated with an increase in resolution and, in the case of a subbottom sonar, a decrease in bottom penetration. Chirp technology, as implemented in the CAP-6600 Chirp II Acoustic Profiling System, reduces this trade-off, providing both high resolution and penetration. System Manual September 1999

33 CAP-6600 Chirp II Acoustic Profiling System 1-13 Image Resolution For subbottom sonar, sound energy transmitted to the seafloor is reflected off the boundaries between layers of different acoustic impedances. The first boundary is between the water and the seafloor itself. As layers of clay, sand and various other sediments succeed each other, they create other interfaces that reflect sound. It is the energy reflected from these boundaries that the system uses to build the image. The resolution of an imaging system is measured by its ability to separate closely spaced objects, i.e., to detect discrete echoes returning from the interfaces between layers. The vertical resolution of an acoustic subbottom profiler refers to the minimum distance that can be visually distinguished in the image produced by the system. A sonar system with a 10 cm resolution will resolve layers that are at least 10 cm apart. Layers spaced closer than 10 cm will be resolved by the system as one layer. In a conventional single-frequency system, the limit of its resolution is determined by the pulse length of the transmitted waveform. In a multi-frequency system, such as the CAP-6600 Chirp II Acoustic Profiling System, it is the bandwidth of the transmitted pulse that sets the system's theoretical resolution. The theoretical sonar range resolution of a conventional single frequency system is calculated by multiplying the length of the pulse by the speed of sound and then dividing the product by 2 to account for the pulse s round trip. range resolution = pulse length x speed of sound / 2 The pulse length equivalent of the de-chirped swept frequency pulse equals the inverse of the bandwidth. pulse length = 1 / bandwidth For example, the duration of a pulse with a bandwidth of 9 khz, which is the bandwidth of a system configured to operate between 1 and 10 khz, is approximately 100 µsec (1/9000 Hz = sec). Travelling at about 1540 m/sec, the sound will traverse approximately 15 cm in 100 µsec. Allowing for the round trip, this results is a one-way distance of 7.5 cm, which is the range resolution. In addition to the frequency and bandwidth of the insonifying beam, other interrelated factors that affect the system's resolution are: SECTION 1 CAP-6600 Overview Chirp Technology

34 1-14 DATASONICS The horizontal width of the beam The tow speed of the vehicle The distance between the tow vehicle and the bottom The nature of the signal processing Figure 1-7 illustrates the vertical resolution achieved with a wide beam transducer that insonifies a large area of the seafloor. The transducer produces a series of reflections that stretch the returned pulse width. The system can distinguish between pulses returning as Echo 1 and Echo 2, but cannot distinguish between Echo 2 and Echo 3. SOURCE ECHO 1 SEAFLOOR FIRST BOUNDARY SECOND BOUNDARY 12 CM 6 CM ECHO 2 ECHO 3 Figure 1-7 Resolving Closely Spaced Layers The larger the area that is insonified, the more the return pulse will be stretched. A 1 millisecond pulse could be stretched to 1.5 or 2 milliseconds. The stretching of the pulse results in the smearing of features that are close together. The transmitted pulse of 1 millisecond corresponds to a 1 khz bandwidth; but the received pulse, stretched to 1.5 millisecond, for example, System Manual September 1999

35 CAP-6600 Chirp II Acoustic Profiling System 1-15 corresponds to a 675 Hz bandwidth. This pulse stretching effectively reduces the bandwidth and with it, the system's ability to resolve layers or objects that are closely spaced. Therefore, narrower beams produce better resolution. Signal processing improves resolution by eliminating or attenuating beam components that would otherwise degrade the resolution. All transmitted narrow beam sound pulses produce side lobes, which contain energy that stretches the pulse and produces undesired echoes from reflections not located in the primary beam. In conventional sidescan and subbottom sonar systems, resolution is lost to stretching by the side lobes. With Chirp technology, the side lobes are greatly reduced through matched-filter processing, which attenuates signals that do not correlate well with the transmitted pulse. The second factor that affects the image quality is the signal-to-noise ratio. As the transmitted pulse travels through the water, its amplitude becomes attenuated and falls below the noise level. The CAP-6600 uses matched-filter correlation processing to improve the signal-to-noise ratio and hence the quality of the sonar images. Chirp Pulse Transmission and Reception Both subbottom channels of the CAP-6600 Chirp II Acoustic Profiling System operate according to the same principles, but one channel transmits and receives low frequency Chirp pulses, and the other transmits and receives high frequency Chirp pulses. The sequence of steps in the transmission and reception of the Chirp pulses for both channels are summarized as follows: 3. Using a 12-bit D/A converter, a linear FM pulse is generated. 4. The signal is sent to a power amplifier which drives the subbottom transducer or transducer array. 5. The subbottom transducer or transducer array transmits the pulse and returns are received by the hydrophone array. Using separate transmitter and receiver arrays preserves linearity and allows simultaneous signal transmission and reception. 6. Reflections at the hydrophone array are filtered and amplified. 7. The sonar signals are digitized with a 16-bit A/D converter. SECTION 1 CAP-6600 Overview Chirp Technology

36 1-16 DATASONICS 8. A digital processor in the workstation, one for each channel, de-chirps (compresses the FM reflections using the matched-filter) the return signals from the subbottom hydrophone. This correlates the received reflections with a compensated replica of the outgoing pulse. The replica used in the matched-filter contains the predetermined phase correction and amplitude weighting to correct anomalies in the transmitting and receiving hardware. Signals that do not resemble the outgoing pulses are attenuated by this type of processing. Compressed returns can be further processed with adjustable Time Varied Gain (TVG) and selectable spreading loss correction for amplitude losses from attenuation and absorption by the water. System Manual September 1999

37 CAP-6600 Chirp II Acoustic Profiling System 2-1 SECTION 2 Specifications SECTION 2 Specifications

38 2-2 DATASONICS System Manual September 1999

39 CAP-6600 Chirp II Acoustic Profiling System 2-3 T he information in this section encompasses the physical and performance specifications of the CAP-6600 Chirp II Workstation and the TTV-170, TTV-190 and TTV-173 Tow Vehicles. Also included are the performance specifications for a hull mount system, which is installed in a hull-mounted sea chest and is permanently wired to the workstation. CAP-6600 Chirp II Workstation The CAP-6600 Chirp II Workstation includes the DSP-661 Processor and the DSP-662 Transceiver. The processor includes an external monitor, trackball, keyboard, and the DSP-661 Processor Software. Both the processor and the transceiver are mounted in a single splash resistant, transportable standard 19" rack. Physical Characteristics Case size: Monitor size: Case weight: Monitor weight: 55.8 cm (22.0 in.) high by 55.8 cm (22.0 in.) wide by 55.8 cm (22.0 in.) deep 35.8 cm (14.1 in.) high by 36.2 cm (14.2 in.) wide by 37.7 cm (14.8 in.) deep 90.0 lb (41 kg) 28.6 lb (13 kg) Software Application: CAP-6600 Processor Software, Chirpscan 2 Operating system: Windows 32-bit Computer Host CPU: Standard I/O ports: Optional I/O ports: Memory: Digital signal processors: Pentium 3 serial, 2 parallel, 1 SCSI 2 serial, 1 parallel 32 MB RAM 32-bit DSP, 2 channels SECTION 2 Specifications CAP-6600 Chirp II Workstation

40 2-4 DATASONICS Graphics processor: Standard data storage: Optional data storage: Power supply: PCI or AGP high resolution Internal hard drive with SCSI interface 3.5" internal floppy drive Magneto-optical drive Other high-density storage devices 300 watts Display Screen size: Screen resolution: 17 in x 1024, 256 colors Main window display: Profile-Channel 1 and 2 Bathymetry-Channel 1 and 2 Signal Stacking-Channel 1 and 2 Charts-Channel 1 and 2 Voltage Signal-Channel 1 and 2 Navigation Chirp II Status Power Requirements Processor power input: Transceiver power input: Monitor Power input: VAC or VAC, Hz, 300 watts, auto sensing VAC or VAC, Hz, 350 watts, auto sensing VAC or VAC, Hz, 150 watts, auto sensing NOTE If a generator is to be used as the power source, a rating of 1500 watts is recommended. System Manual September 1999

41 CAP-6600 Chirp II Acoustic Profiling System 2-5 Input/Output Printer: Operator: Color printer Digital thermal recorder Extended keyboard Trackball Chirp transmit pulse, user selectable output, from 5 msec to 50 msec Transmit rate, user selectable output, from 1/8 sec to 8 sec Transmit power, user adjustable output, up to 4 kw per channel Transmit power control, user selectable attenuation, from 0 db to 21 db Preamplifier, user selectable gain, from 0 db to 30 db External: Channel 1 and Channel 2 matched filtered analog outputs with no TVG applied. Channel 1 and Channel 2 non-chirp analog inputs Key input Key output Analog and Chirp hydrophone inputs Transducer input Bubble pulser input NEMA0183 compatible navigation input User configurable serial or parallel output for exporting or printing data as text, including navigation data Other: SCSI for optional external storage device SECTION 2 Specifications CAP-6600 Chirp II Workstation

42 2-6 DATASONICS TTV-170 Tow Vehicle The TTV-170 Tow Vehicle, which is designed for use on small boats in relatively shallow water, is configured with a low frequency transducer, a high frequency transducer and two hydrophone arrays. The tow vehicle can also be configured for single frequency operation with either the low or high frequency transducer and the hydrophone arrays. Physical Characteristics Construction: Two-part fiberglass shell with 6061 aluminum tow body Dimensions: Weight in air: Weight in water: Tether system: Operating depth: Towing speed: 97 cm (38 in.) long by 46 cm (18 in.) in diameter 101 lb (46 kg) 80 lb (36 kg) Either of two Industry-standard multi-conductor cables: Datasonics TWC-602, Kevlar reinforced, with three twisted/shielded pairs and three conductors for use with separate steel tow cable, or Datasonics TWC-601, Rochester double-armored, with three coaxial pairs and three single conductors for use with winch and slip rings 600 meters 1 to 6 knots operational Low Frequency Sonar Transmitter transducer: Datasonics AT-471 low frequency transducer System Manual September 1999

43 CAP-6600 Chirp II Acoustic Profiling System 2-7 Power output: Frequency range: Transducer radiation: 400 watts, 15% duty cycle at 3.5 khz for 197 db re 1 1 m nominal, 4 kw maximum at reduced duty cycle Sweeps in the 2 khz to 7 khz band 100 conical High Frequency Sonar Transmitter transducer: Power output: Frequency range: Transducer radiation: Datasonics AT-14F7C high frequency transducer 90 watts, 15% duty cycle at 17 khz for 205 db re 1 1 m nominal, 4 kw maximum at reduced duty cycle Sweeps in the 8 khz to 23 khz band 30 conical Sonar Receiver Receiver hydrophone: Frequency band: Two 8-element hydrophone arrays 2 khz to 100 khz TTV-190 Tow Vehicle The TTV-190 Tow Vehicle, which is designed for use in deep water, is configured with four low frequency transducers, a high frequency transducer and a linear hydrophone array. Physical Characteristics Construction: Dimensions: Weight in air: Weight in water: Two-part aluminum reinforced fiberglass 46 cm (18 in.) OD by 163 cm (64 in.) long 340 lb (154 kg) 170 lb (77 kg) SECTION 2 Specifications TTV-190 Tow Vehicle

44 2-8 DATASONICS Tether system: Operating depth: Towing speed: Either of two Industry-standard multi-conductor cables: Datasonics TWC-602, Kevlar reinforced, with three twisted/shielded pairs and three conductors for use with separate steel, tow cable, or Datasonics TWC-601, Rochester double-armored, with three coaxial pairs and three single conductors for use with winch and slip rings 1000 meters 1 to 8 knots operational Low Frequency Sonar Transmitter transducer: Power output: Frequency range: Transducer radiation: Four Datasonics AT-471 low frequency transducers 1.6 kw, 15% duty cycle at 3.5 khz for 209 db re 1 1 m nominal, 4 kw maximum at reduced duty cycle Sweeps in the 2 khz to 7 khz band 45 conical High Frequency Sonar Transmitter transducer: Power output: Frequency range: Datasonics AT-14F7C high frequency transducer 90 watts, 15% duty cycle at 17 khz for 205 db re 1 1 m nominal, 4 kw maximum at reduced duty cycle Sweeps in the 8 khz to 23 khz band Transducer radiation: 30 System Manual September 1999

45 CAP-6600 Chirp II Acoustic Profiling System 2-9 Sonar Receiver Receiver hydrophone: Frequency band: Datasonics AT-473D hydrophone 1.5 khz to 40 khz TTV-173 Tow Vehicle The TTV-173 Tow Vehicle is specifically designed for detecting and tracking buried pipe. The tow vehicle is configured with an array of five transducers and a hydrophone array. The combined transmit and receive beam pattern is a wide, 120 beam in the forward and aft directions and a narrow, 9 beam athwart. Physical Characteristics Construction: Dimensions: Weight in air: Weight in water: Tether system: Operating depth: Towing speed: Aluminum/Delran frame with a Polycarbonate shell 61 cm (24.0 in.) long by 77 cm (30.5 in.) wide 102 lb (46.4 kg) 58 lb (26.4 kg) Either of two Industry-standard multi-conductor cables: Datasonics TWC-602, Kevlar reinforced, with three twisted/shielded pairs and three conductors for use with separate steel, tow cable, or Datasonics TWC-601, Rochester double-armored, with three coaxial pairs and three single conductors for use with winch and slip rings 6000 meters 1 to 8 knots operational SECTION 2 Specifications TTV-173 Tow Vehicle

46 2-10 DATASONICS Sonar Transmitter transducer: Power output: Frequency range: Transducer radiation: Five Datasonics AT-14E2 transducers 800 watts, 15% duty cycle at 17 khz for 212 db re 1 1 m, nominal, 4 kw maximum at reduced duty cycle Sweeps in the 8 khz to 23 khz band 120 fwd/aft, 9 athwart Sonar Receiver Receiver hydrophone: Frequency band: Datasonics AT-473D hydrophone 1.5 khz to 40 khz Hull Mount System For deep water applications a hull mount array of 4 to 16 low frequency transducers and a high frequency transducer can be installed in a hull-mounted sea chest. The transducers perform both the transmit and receive functions. The transducers are wired to a junction box, which is permanently connected to the workstation through the Remote Controlled Transmit/Receive Module. The specifications that follow are for a hull mount system that incorporates 16 low frequency transducers and one high frequency transducer. Low Frequency Sonar Transmitter transducer: Power output: Frequency range: 16 Datasonics AT-471 low frequency transducers 2.3 kw, 15% duty cycle at 3.5 khz for 217 db re 1 1 m nominal, 4 kw maximum at reduced duty cycle Sweeps in the 2 khz to 7 khz band Transducer radiation: 25 System Manual September 1999

47 CAP-6600 Chirp II Acoustic Profiling System 2-11 High Frequency Sonar Transmitter transducer: Power output: Datasonics AT-12D7 high frequency transducer 1 kw, 15% duty cycle at 15 khz for 214 db re 1 1 m nominal, 4 kw maximum at reduced duty cycle Frequency range: Sweeps in the 8 khz to 23 khz band Transducer radiation: 27 Remote Controlled Transmit/Receive Module Control: Preamplifier gain: Preamplifier attenuation: Software control through LPT2 parallel port 46 db in 3 db increments 46 db in 3 db increments SECTION 2 Specifications Hull Mount System

48 2-12 DATASONICS System Manual September 1999

49 CAP-6600 Chirp II Acoustic Profiling System 3-1 SECTION 3 Setup and Deployment SECTION 3 Setup and Deployment

50 3-2 DATASONICS System Manual September 1999

51 CAP-6600 Chirp II Acoustic Profiling System 3-3 S etting up the CAP-6600 Chirp II Acoustic Profiling System begins with the careful unpacking and inspection of the system components. Once this is complete, the CAP-6600 Chirp II Workstation is set up and connected to the tow vehicle. The system is then activated, the DSP-661 Processor Software is started, some predeployment checks are made, and the tow vehicle is deployed. This section encompasses these operations, describes the operator controls and indicators, and includes a startup procedure for getting the system operational quickly. In addition, other system configurations are described for use with an alternate acoustic source and a heave compensator. If a hull mount system is to be installed, refer to APPENDIX B, "Hull Mount System Installation Requirements," for an overview of the requirements for installing a hull mount system and connecting it to the CAP-6600 Chirp II Workstation. NOTE Once the tow vehicle is deployed and the system is operating, refer to SECTION 4, "Operation," for more information on operating the system. Also, for detailed information on the operation of the DSP-661 Processor Software, refer to the DSP-661 Processor Software Manual. Unpacking The CAP-6600 Chirp II Workstation and monitor are shipped in two separate, reusable environmental shipping containers. The tow vehicles are shipped in separate wooden or optional environmental shipping containers. The system documentation and the recording media for the optional high-density storage devices are included in one of the containers or shipped separately. The containers typically include the items listed below; however, be sure to check the packing list to verify the exact contents especially for a hull mount system where the number of containers and their contents will vary, depending on the configuration. Container (1 of 3), environmental shipping: CAP-6600 Chirp II Workstation Keyboard Trackball AC power cables (2) Printer cable (with optional printer only) SCSI cable (with optional external storage device only) SECTION 3 Setup and Deployment Unpacking

52 3-4 DATASONICS Container (2 of 3), environmental shipping: Monitor Monitor cable AC power cable (may be attached to the monitor) Container (3 of 3), wooden or optional environmental shipping: TTV-190 Tow Vehicle 50-meter Kevlar reinforced deck cable Vertical tail fin Horizontal tail fins Tail fin mounting hardware or TTV-170 Tow Vehicle 50-meter Kevlar reinforced deck cable or TTV-173 Tow Vehicle 50-meter Kevlar reinforced deck cable Documentation package (may be included in a shipping container): "CAP-6600 Chirp II Acoustic Profiling System System Manual" "CAP-6600 Chirp II Acoustic Profiling System DSP-661 Processor Software Manual" "Windows" and "System Restore Boot Disk" 3.5" floppy disks "Chirp II Restore," "Windows Operating System," and "Chirp II Software" CDs Manuals for optional components Magneto-optical disks, with magneto-optical drive option only Other high-density storage media, with high-density storage device options only NOTE The TTV-190 Tow vehicle requires some assembly and is shipped with all the required components within the shipping container. The TTV-170 and TTV-173 tow vehicles are shipped complete. System Manual September 1999

53 CAP-6600 Chirp II Acoustic Profiling System 3-5 Inspect the shipping containers for signs of external damage, and after removing the contents, inspect the items for damage before setting up. Do not operate or deploy any equipment that appears to have been damaged in shipping. Immediately report any damage to Datasonics and to the freight carrier. Perform the steps listed below to unpack the CAP-6600 Chirp II Workstation, the monitor and the tow vehicle. 1. Carefully remove the workstation from its shipping container, and then remove the keyboard, the trackball, and all the cables from the compartment that is at the bottom of the container. 2. Carefully remove the monitor, along with the monitor and AC cables, from its shipping container. For a TTV-190 Tow Vehicle only, 3. Using a screw driver, pry off the retaining clips on the lid of the wooden box containing the TTV-190 Tow Vehicle and remove the lid to expose the compartment in the cover of the box. 4. Remove the 50-meter Kevlar reinforced deck cable, the vertical and horizontal tail fins, and the tail fin mounting hardware from the compartment. 5. Remove the lag bolts at the bottom of the box and lift the entire cover to access the tow vehicle. 6. Remove the tiedown straps that secure the tow vehicle. WARNING Use the tow vehicle carrying handles when removing the TTV-190 Tow Vehicle by hand with one person at each handle; use only the tow point when removing the tow vehicle with a crane. 7. Remove the tow vehicle from its container, manually or using a crane. For a TTV-170 or TTV-173 Tow Vehicle only, 8. Remove the 50-meter deck cable, and then remove the tiedown straps and carefully remove the tow vehicle from its shipping container. SECTION 3 Setup and Deployment Unpacking

54 3-6 DATASONICS Workstation Setup Determine where the CAP-6600 Chirp II Workstation will be set up. Figure 3-1 shows the recommended setup configuration and component dimensions. Secure the workstation in place, using tie-downs if necessary, near a VAC or VAC, Hz power source. Be sure the back of the workstation is accessible for connecting the cables. Slide the monitor into the channel on top of the workstation, making sure the swivel base is securely attached to the monitor. 14.1" 22" 22" 22" Figure 3-1 CAP-6600 Chirp II Workstation Recommended Setup System Manual September 1999

55 CAP-6600 Chirp II Acoustic Profiling System 3-7 TTV-190 Tow Vehicle Assembly Only the TTV-190 Tow Vehicle requires some assembly as the tail fins must first be assembled and then installed onto the tow vehicle. This requires the removal of the top shell of the tow vehicle. Follow the steps listed below and refer to Figure 3-2 to perform the assembly. 1. Assemble the vertical fin to the horizontal fins using the two brackets, six sets of the bolts, nuts and lock washers, and twelve of the flat washers. 2. Remove the shackle from the tow vehicle tow point and push the connector pigtail through the hole in the shell and out of the way. 3. Remove the four nuts, one near each of the lifting handles, that attach the top shell to the bottom shell and carefully remove the top shell. 4. Assemble the horizontal tail fin to the tow vehicle using the two remaining sets of bolts, lock washers, and flat washers. 5. Slide the connector pigtail back through the opening in the top shell, reassemble the top shell to the bottom shell, and reattach the shackle. Figure 3-2 Assembling the TTV-190 Tow Vehicle Tail Fins SECTION 3 Setup and Deployment TTV-190 Tow Vehicle Assembly

56 3-8 DATASONICS Workstation Hardware Connections Once the CAP-6600 Chirp II Workstation is secured and the associated cables and devices are connected, it is ready to be connected to a tow vehicle or a hull mount system. Connections to the workstation are made on the front and rear panels of both the processor and the transceiver; however, there are pre-installed cables on the rear panel of the processor, including one that connects to the rear panel of the transceiver. Processor Front and Rear Panel Connections The DSP-661 Processor front panel connectors and their description and use are listed below and are shown in Figure 3-3. Connector KEYBOARD: MOUSE: Description and Use Connects to the keyboard (available on front and back). Connects to the trackball. The DSP-661 Processor rear panel connectors and their description and use are listed below and are shown in Figure 3-4. Connector PRINTER: LPT2: NAV: COM3: SCSI: Description and Use DB-25S parallel port (LPT1) connector that connects to the printer. DB-25S parallel port connector that connects to the Remote Controlled Transmit/Receive Module in a hull mount system. DB-9P serial port (COM1) connector that connects to the navigation system. DB-9P serial port connector that outputs data as text, including navigation data. Optional SCSI connector that connects to an optional external storage device. System Manual September 1999

57 CAP-6600 Chirp II Acoustic Profiling System 3-9 HD INDICATOR POWER INDICATOR KEYBOARD CONNECTOR MOUSE CONNECTOR RESET SWITCH POWER SWITCH 3.5 FLOPPY DRIVE MO DRIVE (Optional) CD ROM DRIVE Figure 3-3 DSP-661 Processor and DSP-662 Transceiver Front Panels VGA OUT: CONTROL LOGIC: DSP-0: DB-15 connector that connects to the monitor. Mass termination connector that connects to the CONTROL LOGIC connector on the rear panel of the transceiver with a pre-installed cable. DB-15 connector on the Channel 0 DSP board that connects to the BURST/RCVR (J6) connector on the burst receiver board with a pre-installed cable. SECTION 3 Setup and Deployment Workstation Hardware Connections

58 3-10 DATASONICS SCSI NAV PRINTER KEYBOARD DSP-0 DSP-1 CONTROL LOGIC BURST/ RCVR (J6) COM3 IQ VAC OUT VAC IN VGA OUT LPT2 BURST/RCVR (J7) CONTROL LOGIC Figure 3-4 DSP-661 Processor and DSP-662 Transceiver Rear Panels DSP-1: BURST/RCVR (J6): BURST/RCVR (J7): DB-15 connector on the Channel 1 DSP board that connects to the BURST/RCVR (J7) connector on the burst receiver board with a pre-installed cable. DB-15 connector on the burst receiver board that connects to the DSP-0 connector with a pre-installed cable. DB-15 connector on the burst receiver board that connects to the DSP-1 connector with a pre-installed cable. System Manual September 1999

59 CAP-6600 Chirp II Acoustic Profiling System 3-11 Transceiver Front and Rear Panel Connections The DSP-662 Transceiver front panel connectors are all BNC connectors and are shown in Figure 3-3 on page 3-9. Their description and use are listed below. For information on the CH1 ANALOG IN, CH2 ANALOG IN and DELAY KEY IN switches called out below, refer to "Transceiver Operator Functions" on page Connector CH1 ANALOG IN: CH2 ANALOG IN: EXT KEY IN: KEY OUT: DELAY KEY IN: Description and Use Inputs an external analog signal of +/- 3 volts maximum when the CH1 ANALOG IN switch is switched to ON. Used to input analog signals from an external source such as a Datasonics SPR-1200 Seismic Profiling System ("Bubble Pulser") for processing by the workstation. Inputs an external analog signal of +/-3 volts maximum when the CH2 ANALOG IN switch is switched to ON. Used to input analog signals from an external source such as a Bubble Pulser for processing by the workstation. Inputs an external 0-5 volt, 100 µsec minimum pulse width signal that keys the transceiver. Used to key the transceiver from an external source such as a Bubble Pulser. Outputs a 0-5 volt, 100 µsec wide pulse at the start of each transmit cycle. Used to key a heave compensator. Inputs an external 0-5 volt, 100 µsec minimum pulse width signal that keys the transmitter when the DELAY KEY IN switch is switched to ON. Used to input the delayed key output of a heave compensator. SECTION 3 Setup and Deployment Workstation Hardware Connections

60 3-12 DATASONICS CH1 ANALOG OUT: CH2 ANALOG OUT: ANALOG HYDROPHONE: CHIRP HYDROPHONE: PREAMP IN: PREAMP OUT: Outputs the matched filtered analog output of Channel 1, which is the low frequency channel, with no TVG applied. Used as the input to a digital thermal recorder. Also outputs the amplified and filtered analog input of CH1 ANALOG IN, without TVG, when the CH1 ANALOG IN switch is switched to ON. Outputs the matched filtered analog output of Channel 2, which is the high frequency channel, with no TVG applied. Used as the input to a digital thermal recorder. Also outputs the amplified and filtered analog input of CH2 ANALOG IN, without TVG, when the CH2 ANALOG IN switch is switched to ON. Outputs the analog signals that are input from the hydrophone array connected to the BPR connector on the rear panel of the transceiver. Can be used as the input to a preamplifier. Outputs the analog signals that are input from the hydrophone array connected to the TRANSDUCER connector on the rear panel of the transceiver. It is the same signal that is output on the HYDROPHONE connector on the rear panel of the transceiver. Can be used as the input to a preamplifier. Inputs an analog signal. Can be used to input the ANALOG HYDROPHONE or the CHIRP HYDROPHONE output. Outputs the amplified analog input of PREAMP IN. Can be used as an input to the CH1 ANALOG IN or the CH2 ANALOG IN connector. System Manual September 1999

61 CAP-6600 Chirp II Acoustic Profiling System 3-13 The DSP-662 Transceiver rear panel connectors are all BNC connectors except the BPR and TRANSDUCER connectors, which are 10-pin male and female Amphenol connectors, respectively. The connectors are shown in Figure 3-4 on page 3-10, and their function and use are listed below. Connector Description and Use CH1 RECEIVE: Inputs an analog signal to the Channel 1 receiver input. Used for calibration, testing or troubleshooting the Channel 1 receiver. CH2 RECEIVE: Inputs an analog signal to the Channel 2 receiver input. Used for calibration, testing or troubleshooting the Channel 2 receiver. HYDROPHONE: BPR: TRANSDUCER: CONTROL LOGIC: Outputs the analog signals that are input from the hydrophone array connected to the TRANSDUCER connector on the rear panel of the transceiver. It is the same signal that is output on the CHIRP HYDROPHONE connector on the front panel of the transceiver. Can be used as the input to a preamplifier. Connects to the Bubble Pulser hydrophone array and supplies power to the array preamplifier. Used to connect the Bubble Pulser hydrophone array output to the ANALOG HYDROPHONE connector on the front panel of the transceiver. Connects to the tow vehicle or to the Remote Controlled Transmit/Receive Module in a hull mount system. Mass termination connector that connects to the CONTROL LOGIC connector on the rear panel of the processor with a pre-installed cable. SECTION 3 Setup and Deployment Workstation Hardware Connections

62 3-14 DATASONICS Connecting the Workstation When all the connectors have been identified, perform the steps listed below to make the connections to the workstation. WARNING Before making any connections to the workstation, be sure the transceiver is turned off by verifying that the POWER switch on the front panel of the transceiver is off. Refer to "Workstation Operator Functions" on page 3-16 for a description of the front panel controls. 1. Connect the keyboard to the KEYBOARD connector and the trackball to the MOUSE connector on the front panel of the processor and position them as shown in Figure 3-1 on page Connect the monitor cable to the VGA OUT connector on the rear panel of the processor, and to the monitor. 3. Be sure the monitor power switch is off and connect the monitor AC power cable to the monitor if it is not already attached, and to the VAC OUT connector on the rear panel of the processor. NOTE The CAP-6600 Chirp II Workstation is autosensing and does not require special switch settings for 110 VAC or 220 VAC operation. The workstation will operate properly using either of these standard VAC power sources. 4. Connect one AC power cable to the VAC IN connector on the rear panel of the processor, and the other to the VAC IN connector on the rear panel of the transceiver. Connect both cables to the VAC or VAC, Hz power source. The following processor rear panel connections are for optional equipment: 5. Connect the printer cable to the PRINTER connector. 6. Connect the Remote Controlled Transmit/Receive Module in a hull mount system to the LPT2 connector. 7. Connect the navigation output from the shipboard navigation system to the NAV connector. 8. Connect any external SCSI storage devices to the SCSI connector. System Manual September 1999

63 CAP-6600 Chirp II Acoustic Profiling System 3-15 Connecting the Tow Vehicle One end of the 50-meter Kevlar reinforced deck cable connects to the DSP-662 Transceiver, and the other end connects to the tow vehicle. Follow the steps listed below to connect the deck cable. NOTE When connecting a different tow vehicle or an AT-471 transducer array, refer to "Changing the Transformer Jumpers" on page 6-16 for instructions on how to reconfigure or verify the Transformer Jumper board jumper configuration for the new tow vehicle or the transducer array. 1. Connect the 50-meter Kevlar reinforced deck cable 10-pin male Amphenol connector to the TRANSDUCER connector on the rear panel of the transceiver. 2. If either the TTV-170 or the TTV-190 tow vehicle is to be connected, connect the opposite end of the deck cable to the tow vehicle as shown in Figure 3-5. Note that the tow cable in the figure will be attached later. If the TTV-173 tow vehicle is to be connected, connect the opposite end of the deck cable to the tow vehicle as shown in Figure 3-6. Note that the tow cable in the figure will be attached later. However, the TTV-173 Tow Vehicle also includes a collar that can be used to secure a pole for over-the-side mounting. In this case, only the deck cable is used. 50-METER KEVLAR REINFORCED DECK CABLE TOW CABLE Figure 3-5 TTV-170 or TTV-190 Tow Vehicle Cable Connection SECTION 3 Setup and Deployment Workstation Hardware Connections

64 3-16 DATASONICS COLLAR FOR OVER-THE-SIDE MOUNTING 50-METER KEVLAR REINFORCED DECK CABLE TOW CABLE Figure 3-6 TTV-173 Tow Vehicle Cable Connection Workstation Operator Functions There are a number of important operator functions that are accessible on the front panel of the DSP-661 Processor, and the front and rear panels of the DSP-662 Transceiver. They include the system operating controls, indicators and storage devices. Processor Operator Functions The DSP-661 Processor front panel functions and their description and use are listed below and are shown in Figure 3-3 on page 3-9. Function HD indicator: RESET switch: POWER switch: POWER indicator: Description And Use A red indicator that is illuminated when the processor is accessing the hard drive. A push button switch that resets the processor. A rocker switch that turns the processor on or off. The processor turns on when "I" is pressed, and off when "O" is pressed. A green indicator that is illuminated when the processor is on. System Manual September 1999

65 CAP-6600 Chirp II Acoustic Profiling System 3-17 CD ROM drive: Optical read only drive for loading programs and data. 3.5" Floppy drive: Accepts 3.5" floppy diskettes for alternate boot-up, loading programs and files, and making back-up copies. The drive is recognized as the A drive. Magneto-optical (MO) drive: Transceiver Operator Functions An optional high-density storage device that uses optical read/write disks for recording and playing back data. The DSP-662 Transceiver front panel functions and their description and use are listed below and are shown in Figure 3-3 on page 3-9. For information on the CH1 ANALOG IN, CH2 ANALOG IN, DELAY KEY IN, EXT KEY IN, and PREAMP IN connectors called out below, refer to "Transceiver Front and Rear Panel Connections" on page Function POWER switch: POWER indicator: TRANSMIT CH1 LED: TRANSMIT CH2 LED: CH 1 ANALOG IN switch: Description And Use A rocker switch that turns the transceiver on or off. The transceiver turns on when "I" is pressed, and off when "0" is pressed. A red indicator that is illuminated when the transceiver is on. A green indicator that flashes at the repetition rate of the Channel 1 transmitter. A green indicator that flashes at the repetition rate of the Channel 2 transmitter. A toggle switch that enables the CH1 ANALOG IN input when switched to ON. When switched to OFF, the CH1 ANALOG IN input is disabled and signals are input from the tow vehicle or the hull mount system. SECTION 3 Setup and Deployment Workstation Operator Functions

66 3-18 DATASONICS CH 2 ANALOG IN switch: A toggle switch that enables the CH2 ANALOG IN input when switched to ON. When switched to OFF, the CH2 ANALOG IN input is disabled and signals are input from the tow vehicle or the hull mount system. DELAY KEY IN switch: A toggle switch that enables the DELAY KEY IN input when switched to ON. When switched to OFF, the DELAY KEY IN input is disabled and the transceiver is keyed either internally or from a key input to EXT KEY IN. PREAMP GAIN db switch: A rotary switch that selects either 0, 15, or 30 db of gain, which is applied to the PREAMP IN input. The DSP-662 Transceiver rear panel functions and their description and use are listed below and are shown in Figure 3-4 on page Function CH1 HYDROPHONE/ T/R switch: CH2 HYDROPHONE/ T/R switch: Description And Use A toggle switch that activates the Channel 1 Transmit/Receive function when switched to T/R. This allows the transceiver s Channel 1 to transmit and receive from the same transducer, hence providing increased sensitivity for deep water applications. When switched to HYDROPHONE, the transceiver inputs the tow vehicle s hydrophone output. A toggle switch that activates the Channel 2 Transmit/Receive function when switched to T/R. This allows the transceiver s Channel 2 to transmit and receive from the same transducer, hence providing increased sensitivity for deep water applications. When switched to HYDROPHONE, the transceiver inputs the tow vehicle s hydrophone output. System Manual September 1999

67 CAP-6600 Chirp II Acoustic Profiling System 3-19 System Startup After all the connections have been made, the processor is ready to be turned on and the Windows operating system and DSP-661 Processor Software started. Once the software is operational, the setup parameters are configured, the transceiver is activated, the predeployment checks are made, and the tow vehicle is launched. Activating the DSP-661 Processor Perform the steps listed below to turn on the processor, start Windows and start the DSP-661 Processor Software. Many of the tasks that are performed in Windows call for the use of the trackball. When the instructions call for "clicking" in a window, "double clicking" an icon or choosing a menu item, it is the left trackball button that is pressed. WARNING Be sure the transceiver is turned off by verifying that the POWER switch on the front panel of the transceiver is off. Refer to "Workstation Operator Functions" on page 3-16 for a description of the front panel controls. 1. Turn on any optional external devices such as SCSI storage devices and printers. 2. Turn on the monitor. 3. Turn on the processor by pressing "I" on the POWER switch. The POWER indicator will light, and the HD indicator will flash as the processor s internal hard drive is accessed. After a brief time, the Windows desktop is displayed. 4. In the Windows desktop double-click the Chirp2 icon ( ) to choose it and start the CAP-6600 Processor Software. The Main and Chirp 2 Controls windows open as shown in Figure 3-7. Configuring the Setup Parameters If not already done so during prior use of the system, it may be necessary to configure some of the setup parameters. The setup parameters include the navigation, recording and display settings. SECTION 3 Setup and Deployment System Startup

68 3-20 DATASONICS Figure 3-7 The Main and Chirp 2 Controls Windows Configuring the Navigation Parameters If a shipboard navigation system is or will be connected to the NAV connector, which is the COM1 serial port of the DSP-661 Processor, perform the steps listed below to configure or verify the navigation parameters. 1. Select File from the menu bar, select Comm Ports, and then choose Comm Port Setup. The Communication Port Setup dialog box shown in Figure 3-8. opens. 2. In the Setup area of the Communication Port Setup dialog box, select COM1. 3. In the Baud Rate area select In the Data Bits area select In the Stop Bits area select In the Parity area select NONE. System Manual September 1999

69 CAP-6600 Chirp II Acoustic Profiling System 3-21 Figure 3-8 The Communication Port Setup Dialog Box NOTE If a custom string is to be used for the navigation template, refer to the DSP-661 Processor Software Manual for more information. 7. In the Nav Port area select COM1. 8. In the Aux Port area select COM1. 9. Check the Nav ON check box. 10. Clear the Display Degrees check box. 11. In the External Comments Template area check the Warning Sound for incoming Comment check box. 12. Click OK to close the Communication Port Setup dialog box and save the settings. SECTION 3 Setup and Deployment System Startup

70 3-22 DATASONICS Configuring the Recording Parameters Perform the steps listed below to configure or verify the recording parameters. 1. Select File from the menu bar, and then choose Record. The Record Setup dialog box shown in Figure 3-9 opens. 2. In the Record Setup dialog box, click Display Only. The Recording Data Rate dialog box shown in Figure 3-10 opens. 3. In the Recording Data Rate dialog box, check the User Define check box. The Default check box clears automatically. 4. In the User Define Data Rate area of the Recording Data Rate dialog box, select The Data Rate display should indicate "2048/ping, 8192/sec." Figure 3-9 The Record Setup Dialog Box NOTE Refer to SECTION 4, "Operation," for more information on the Recording Data Rate dialog box settings as the optimal settings depend on the transmit repetition rate and other factors. 5. Click OK to save the settings and close the Recording Data Rate dialog box. The message "DSP Loading... Please Wait..." is displayed for a few seconds. If it is the first time the DSP-661 Processor Software has been started, the default display setup consisting of the Profile - CH1+CH2 window opens next, as shown in Figure After a short time, and only if navigation data are not available, or if a shipboard navigation system is not connected to the NAV connector of the DSP-661 Processor, Figure 3-10 The Recording Data Rate Dialog Box System Manual September 1999

71 CAP-6600 Chirp II Acoustic Profiling System 3-23 the Chirp 2 Navigation Warning dialog box opens with a message warning that there is no navigation data: Click OK to close the Chirp 2 Navigation Warning dialog box. This dialog box will appear every two minutes until there is navigation data or the Nav ON check box is cleared in the Communication Port Setup dialog box. Refer to "Configuring the Navigation Parameters" on page 3-20 for instructions on how to open the Communication Port Setup dialog box. Figure 3-11 The Default Display Setup SECTION 3 Setup and Deployment System Startup

72 3-24 DATASONICS Configuring the Display Parameters In order to simplify the display during the predeployment checks, the basic display setup consisting of the Profile - CH1+CH2 window should be opened. However, if it is the first time the DSP-661 Processor Software has been started, this display opens automatically when configuring the recording parameters as described in "Configuring the Recording Parameters" on page In addition, the display gain, which amplifies the return signals for display, and the display threshold, which sets the amount of information displayed, may require setting. Perform the steps listed below to open the basic display setup and to configure or verify the display gain and threshold parameters. 1. Select Window from the menu bar, select Default Setup, and then choose Basic Setup. The basic display setup opens with only the Profile - CH1+CH2 window open. 2. Select Display from the menu bar, and then choose Display Gain. The Display Gain Setup window shown in Figure 3-12 opens over the Chirp 2 Controls window. The display gain is applied to the display only and does not affect the recorded data. The applied gain is non-linear, applying more gain to the weaker signals than to the stronger signals. 3. Click anywhere in the Profile - CH1+CH2 window to make it active. 4. In the Current Gain area of the Display Gain Setup window, use the scroll bar to set the gain to Non-Linear, 22 db. 5. In the Display Threshold area use the CH 1 and CH 2 scroll bars to set the Channel 1 and Channel 2 display thresholds to Click OK to save the settings and close the Display Gain Setup window. Figure 3-12 The Display Gain Setup Window System Manual September 1999

73 CAP-6600 Chirp II Acoustic Profiling System 3-25 Activating the DSP-662 Transceiver If not already done so during prior use of the system, it may be necessary to set the front and rear panel switches on the DSP-662 Transceiver to their default settings and to configure the settings in the Chirp 2 Controls window. These settings are required for the predeployment checks. Refer to Figure 3-13 and perform the steps listed below to turn on the transceiver and verify the switch settings. REAR PANEL SWITCH SETTINGS FRONT PANEL SWITCH SETTINGS Figure 3-13 DSP-662 Transceiver Default Switch Settings 1. Turn on the transceiver by pressing "I" on the POWER switch. The POWER indicator will light. 2. On the front panel of the transceiver, switch the CH 1 ANALOG IN switch to OFF. 3. Switch the CH2 ANALOG IN switch to OFF. 4. Switch the DELAY KEY IN switch to OFF. 5. Switch the PREAMP GAIN db switch to On the rear panel of the transceiver, switch the CH 1 HYDROPHONE/T/R switch to HYDROPHONE. 7. Switch the CH 2 HYDROPHONE/T/R switch to HYDROPHONE. SECTION 3 Setup and Deployment System Startup

74 3-26 DATASONICS In the Chirp 2 Controls window, which is shown in Figure 3-14, perform the steps listed below to configure the control settings. 1. In the Trigger Source area of the Controls section of the Chirp 2 Controls window, select Internal. 2. Use the Trig Rate scroll bar to set the transmit repetition rate to s. 3. In the Hardware Gain area use the Ch1 and Ch2 scroll bars to set the Channel 1 and Channel 2 receiver gains to 0 db. 4. In the Power Controls area use the Ch1 and Ch2 scroll bars to set the Channel 1 and Channel 2 transmitter attenuations to 0 db. 5. In the Chirp Length area use the Ch1 and Ch2 scroll bars to set the Channel 1 and Channel 2 Chirp pulse lengths to 5 ms. 6. Click the SET button. The tow vehicle will begin transmitting at four times a second. WARNING Do not allow the tow vehicle to transmit continuously on deck for more than one half hour. 7. In the Track Channel area of the Bottom Tracking-TVG section of the Chirp 2 Controls window, select CH Select Auto. 9. Use the Track Sensitivity scroll bar to set the track sensitivity to 45%. 10. Use the Holdoff scroll bar to set the holdoff to 2 m. 11. Use the TVG Ch 1 and Ch 2 scroll bars to set the Channel 1 and Channel 2 TVGs to Use the Smooth scroll bar to set smoothing to 0%. Figure 3-14 The Chirp 2 Controls Window System Manual September 1999

75 CAP-6600 Chirp II Acoustic Profiling System 3-27 Performing the Predeployment Checks The predeployment checks are recommended to verify that the system is functioning properly on deck before the tow vehicle is deployed. The checks are easy to perform and involve several procedures: activating the system diagnostics which produces a Chirp pattern test that checks the receivers, listening for the transmitted pulses from each of the transducers one at a time, and tapping under the tow vehicle to induce an acoustic signal in the hydrophone array. To begin the predeployment checks, first verify that the tow vehicle transducers are transmitting, and then perform the steps listed below. 1. Select Tools from the menu bar, select Diagnose, and then choose System Diagnose to start the Chirp pattern test. The tow vehicle will stop transmitting and a Chirp pattern will begin to scroll across the CH 1 and CH 2 profile displays in the Profile - CH1+CH2 window. 2. Examine the profile displays in the Profile - CH1+CH2 window. After several minutes the displays should look similar to those shown in Figure 3-15 with black and gray horizontal bars of gradually increasing intensity. 3. To return to normal operation, again select Tools from the menu bar, select Diagnose, and then choose System Diagnose. The tow vehicle will begin transmitting again and the Chirp pattern test will stop. For the remaining steps, if the TTV-190 Tow Vehicle is the connected tow vehicle, refer to Figure 3-16 for the specific location of the transducers and the hydrophone array. 4. Turn off the Channel 1 transmitter by using the Ch1 scroll bar in the Power Controls area of the Chirp 2 Controls window to set the Channel 1 transmitter attenuation to OFF. The Channel 1 transmitter will stop transmitting. 5. Listen for the transmitted pulses from the high frequency transducer in the tow vehicle. When the transmissions have been verified, turn the Channel 1 transmitter back on by using the Ch1 scroll bar in the Power Controls area of the Chirp 2 Controls window to set the Channel 1 transmitter attenuation to 0 db. The Channel 1 transmitter will begin transmitting again. 6. Turn off the Channel 2 transmitter by using the Ch2 scroll bar in the Power Controls area of the Chirp 2 Controls window to set the Channel 2 transmitter attenuation to OFF. The Channel 2 transmitter will stop transmitting. SECTION 3 Setup and Deployment System Startup

76 3-28 DATASONICS HORIZONTAL BARS Figure 3-15 The Chirp Pattern Test Display 7. Listen for the transmitted pulses from the low frequency transducer in the tow vehicle. When the transmissions have been verified, turn the Channel 2 transmitter back on by using the Ch2 scroll bar in the Power Controls area of the Chirp 2 Controls window to set the Channel 2 transmitter attenuation to 0 db. The Channel 2 transmitter will begin transmitting again. 8. With a wrench or similar blunt object, perform the tap test by rapidly tapping the underside of the tow vehicle for 15 to 20 seconds in the area of the hydrophone arrays. 9. Examine the profile displays in the Profile - CH1+CH2 window. The displays should look similar to those shown in Figure 3-17 with vertical streaks displayed in both the CH 1 and CH 2 profile displays. System Manual September 1999

77 CAP-6600 Chirp II Acoustic Profiling System 3-29 LOW FREQUENCY TRANSDUCERS HIGH FREQUENCY TRANSDUCER HYDROPHONE ARRAY Figure 3-16 Location of TTV-190 Transducers and Hydrophone Array If the vertical streaks cannot be seen, temporarily increase the Channel 1 and Channel 2 receiver gains using the Ch1 and Ch2 scroll bars in the Hardware Gain area of the Chirp 2 Controls window. If required, also increase the Channel 1 and Channel 2 TVGs using the Ch 1 and Ch 2 scroll bars in the Bottom Tracking-TVG section of the Chirp 2 Controls window. After the vertical streaks have been verified, return the Channel 1 and Channel 2 receiver gains and TVGs back to their original settings. 10. If navigation data are available, examine the Navigation-Status area of the Chirp 2 Controls window. Navigation data should be present. 11. Select File from the menu bar, and then choose Stop. The predeployment checks are complete, and the tow vehicle can now be deployed. However, if the tow vehicle is not to be deployed immediately, turn off the transceiver. In addition, should it be required to exit the DSP-661 Processor Software, perform the steps listed below. 1. Select File from the menu bar, and then choose Exit. A window opens asking whether to save the setup. 2. Click Yes to save the display setup as the default setup, or click No to not save the display setup. The DSP-661 Processor Software exits. SECTION 3 Setup and Deployment System Startup

78 3-30 DATASONICS VERTICAL STREAKS Figure 3-17 The Tap Test Display System Manual September 1999

79 CAP-6600 Chirp II Acoustic Profiling System 3-31 Tow Vehicle Deployment Before deploying the tow vehicle, a choice of tow cable and its length must be made based on the desired operating depth of the tow vehicle. Once a tow cable is selected, the cable is attached to the tow vehicle s tow point, and the tow vehicle is hoisted and checked for proper balance. When the proper balance is achieved, the tow vehicle is launched from the stern of the vessel using a boom or an A-frame and a winch. Then the tow vehicle is lowered to a depth of only a few meters while its operation is verified. WARNING Do not use the deck cable to hoist or tow the tow vehicle. Although the cable is Kevlar reinforced and has a strength member, it is not to be used for towing. Only a separate steel cable or armored multi-conductor tow cable may be used for this purpose. Selecting a Tow Cable If the desired tow vehicle towing depth exceeds that which the tow vehicle can connect to the processor with the standard 50-meter Kevlar reinforced deck cable, either a longer deck cable or an armored multi-conductor tow cable must be used. The required length of the armored multi-conductor tow cable depends on the anticipated towing speed and tow vehicle depth. For relatively shallow applications the standard Datasonics TWC-601, 150-meter armored multi-conductor tow cable can be used. Table 3-1 lists the approximate operating depth at which the tow vehicle is expected to tow for various towing speeds using this cable. Table 3-1 Tow Speed vs. Depth Tow Speed (knots) Tow Vehicle Depth (meters) SECTION 3 Setup and Deployment Tow Vehicle Deployment

80 3-32 DATASONICS For towing at deeper depths a longer armored multi-conductor tow cable is required. Table 3-2 provides a rough guide for determining the required armored multi-conductor tow cable length verses towing speed for towing the tow vehicle at a depth of 600 meters. For more shallow applications, calculate the required cable length by using the ratio of the desired tow vehicle operating depth in meters to 600 meters, then multiply this ratio by the cable length for the selected tow speed shown in the table. For example, if the towing depth is to be 300 meters, then the ratio is 300/600, or 0.5. Next, if the towing speed is to be 4 knots, multiply this ratio by 1500 meters. Therefore, the required cable length is 750 meters. Table 3-2 Tow Speed vs. Cable Length Tow Speed (knots) Cable Length (meters) Connecting the Tow Cable If the standard 50-meter Kevlar reinforced deck cable is not to be used to connect to the tow vehicle, begin with Step 1 below to disconnect the deck cable and connect the armored multi-conductor tow cable. If the deck cable is to be used to connect to the tow vehicle, leave the cable connected and begin with Step 2. In addition, be sure to use a steel tow cable, not the 50-meter Kevlar reinforced deck cable, to tow the tow vehicle. WARNING If the deck cable is to be disconnected from the tow vehicle, be sure the transceiver is turned off by verifying that the POWER switch on the front panel of the transceiver is off. Refer to "Workstation Operator Functions" on page 3-16 for a description of the front panel controls. System Manual September 1999

81 CAP-6600 Chirp II Acoustic Profiling System After turning off the transceiver, disconnect the deck cable from the tow vehicle and the transceiver. Connect, but do not yet attach, the armored multi-conductor tow cable to the tow vehicle and connect the winch s deck cable to the transceiver. NOTE If an armored multi-conductor tow cable is to be used, it is recommended that the steps in "Activating the DSP-662 Transceiver" on page 3-25 and "Performing the Predeployment Checks" on page 3-27 be repeated with the cable connected. 2. For the TTV-170 or the TTV-190 tow vehicle refer to Figure 3-5 on page 3-15 and attach the steel tow cable or the armored multi-conductor tow cable to the middle hole on the tow point at the top of the tow vehicle using the supplied shackle or tow cable retention bolt. Do not secure the tow cable at this time, as depending on the distributed weight of the tow vehicle, it may be necessary to use a different hole to balance the tow vehicle properly before deployment. For the TTV-173 Tow Vehicle, refer to Figure 3-6 on page 3-16 and attach the tow cable as shown. If the deck cable is used to connect to the tow vehicle, do not secure it at this time. WARNING Do not use any of the carrying handles to hoist the TTV-190 Tow Vehicle. Only the tow point should be used for this purpose. 3. Hoist the tow vehicle and check for proper balance. The tow vehicle should hang with its nose slightly above the tail. Reconnect the tow cable to the forwardmost hole on the tow point if the nose is down, or the next hole aft, if the nose is much higher than the tail. 4. When the tow vehicle is properly balanced, secure the tow cable to the tow point by tightening the shackle bolt or tow cable retention bolt. If a shackle bolt is used, secure the bolt to the shackle with tie-wraps or seizing wire to prevent the bolt from dropping out should it loosen. 5. If the deck cable is used to connect to the tow vehicle, secure it to the tow cable with a shackle and tie wraps. SECTION 3 Setup and Deployment Tow Vehicle Deployment

82 3-34 DATASONICS Launching the Tow Vehicle Perform the steps listed below to launch the tow vehicle and verify its operation. It is recommended that the tow vehicle be launched from the stern of the vessel using a boom or an A-frame. If the DSP-661 Transceiver has been turned off and the DSP-661 Processor Software has been exited, first restart the software, and then turn on the transceiver 1. Lower the tow vehicle into the water. For the TTV-190 Tow Vehicle loop lines through the forward port and starboard carrying handles to stabilize the tow vehicle while it is suspended. 2. Submerge the tow vehicle to a depth of two or three meters, and then begin cruising at two to four knots. 3. Select File from the menu bar, and then choose Record. The Record Setup dialog box shown in Figure 3-9 on page 3-22 opens. 4. In the Record Setup dialog box, click Display Only. The Recording Data Rate dialog box shown in Figure 3-10 on page 3-22 opens. 5. Click OK to close the Recording Data Rate dialog box. The message "DSP Loading... Please Wait..." is displayed for a few seconds. If it is the first time the DSP-661 Processor Software has been started, the default display setup consisting of the Profile - CH1+CH2 window opens as shown in Figure 3-11, and profile data are displayed. After a short time, and only if navigation data are not available, or if a shipboard navigation system is not connected to the NAV connector of the DSP-661 Processor, the Chirp 2 Navigation Warning dialog box opens with a message warning that there is no navigation data: Click OK to close the Chirp 2 Navigation Warning dialog box. This dialog box will appear every two minutes until there is navigation data or the Nav ON check box is cleared in the Communication Port Setup dialog box. Refer to "Configuring the Navigation Parameters" on page 3-20 for instructions on how to open the Communication Port Setup dialog box. System Manual September 1999

83 CAP-6600 Chirp II Acoustic Profiling System Examine the profile displays in the Profile - CH1+CH2 window. If the bottom is within range of the sonar, the sonar images will begin scrolling across the CH 1 and CH 2 profile displays in the window. NOTE The settings in the Chirp 2 Controls window may require modification, depending on the towing depth, the transmit repetition rate and operator preferences. Some basic operating instructions are provided in SECTION 4, "Operation," and detailed instructions on the operation of the DSP-661 Processor Software are provided in the DSP-661 Processor Software Manual. An example of CAP-6600 Chirp II sonar images is shown in Figure If the tow vehicle remains stable and is operating correctly, it can be lowered to its operational depth and the recording of data can begin. Refer to SECTION 4, "Operation," for more information on the controls in the Chirp 2 Controls window and how to adjust them, and instructions on how to set the recording parameters and record data. To stop the acquisition and processing of profile data and exit the DSP-661 Processor Software, perform the steps listed below. 1. Select File from the menu bar, and then choose Stop 2. Select File from the menu bar, and then choose Exit. A window opens asking whether to save the setup. 3. Click Yes to save the display setup as the default setup, or click No to not save the display setup. The DSP-661 Processor Software exits. SECTION 3 Setup and Deployment Tow Vehicle Deployment

84 3-36 DATASONICS Figure 3-18 Example CAP-6600 Chirp II Sonar Images Other System Configurations The CAP-6600 Chirp II Acoustic Profiling system can be configured with other external devices and seismic sources. For example, the hydrophone output of a Datasonics SPR-1200 Seismic Profiling System or an alternate non-chirp seismic source can be connected to receive, process, record and display profile data. In addition, a heave compensator, which minimizes the effects of tow vehicle heave, can be connected. These devices all connect to the DSP-662 Transceiver. Refer to "Transceiver Front and Rear Panel Connections" on page 3-11 for a description of the connectors and their functions. Connect the external devices or alternate seismic sources after making all the connections to the workstation as described in "Connecting the Workstation" on page 3-14 System Manual September 1999

85 CAP-6600 Chirp II Acoustic Profiling System 3-37 Connecting an SPR-1200 Seismic Profiling System ("Bubble Pulser") The Datasonics SPR-1200 Seismic Profiling System ("Bubble Pulser") hydrophone array output can be connected either to Channel 1 or to Channel 2 of the DSP-662 Transceiver. In addition, the Bubble Pulser hydrophone array output can be preamplified using the preamplifier in the transceiver. Perform the steps listed below to connect the Bubble Pulser hydrophone array to the transceiver without preamplification. 1. Connect the interface cable that is supplied with the Bubble Pulser to BPR on the rear panel of the transceiver and to the Bubble Pulser hydrophone cable. 2. Connect ANALOG HYDROPHONE to CH1 ANALOG IN or to CH2 ANALOG IN. 3. Switch the corresponding CH1 ANALOG IN or CH2 ANALOG IN switch to ON. 4. Connect KEY OUT on the transceiver to KEY IN on the Bubble Pulser power supply. Perform the steps listed below to connect the Bubble Pulser hydrophone array to the transceiver with preamplification. 1. Connect the interface cable that is supplied with the Bubble Pulser to BPR on the rear panel of the transceiver and to the Bubble Pulser hydrophone cable. 2. Connect ANALOG HYDROPHONE to PREAMP IN. 3. Connect PREAMP OUT to CH1 ANALOG IN or to CH2 ANALOG IN. 4. Switch the corresponding CH1 ANALOG IN or CH2 ANALOG IN switch to ON. 5. Switch the PREAMP GAIN db switch to the required gain setting. 6. Connect KEY OUT on the transceiver to KEY IN on the Bubble Pulser power supply. 7. Refer to "Setting Up the Channel 1 Bandpass Filter" on page 3-39 to configure the DSP-661 Processor Software for a Bubble Pulser connected to Channel 1, or to "Setting Up the Channel 2 Bandpass Filter" on page 3-40 for a Bubble Pulser connected to Channel 2. SECTION 3 Setup and Deployment Other System Configurations

86 3-38 DATASONICS Connecting an Alternate Seismic Source The alternate source can be connected either to Channel 1 or to Channel 2 of the DSP-662 Transceiver. Alternate seismic sources are any non-chirp sources including boomers and sparkers. The source can be keyed by the transceiver, or the transceiver can be keyed by the source. In addition, the non-chirp seismic source hydrophone output can be preamplified using the preamplifier in the transceiver. Perform the steps below to connect the source without preamplification. 1. Connect the source hydrophone to CH1 ANALOG IN or to CH2 ANALOG IN. 2. Switch the corresponding CH1 ANALOG IN or CH2 ANALOG IN switch to ON. 3. If it is required that the source key the transceiver, connect EXT KEY IN on the transceiver to KEY OUT on the source. If it is required that the transceiver key the source, connect KEY OUT on the transceiver to KEY IN on the source. Perform the steps below to connect the source with preamplification. 1. Connect the source hydrophone to PREAMP IN. 2. Connect PREAMP OUT to CH1 ANALOG IN or to CH2 ANALOG IN. 3. Switch the corresponding CH1 ANALOG IN or CH2 ANALOG IN switch to ON. 4. Switch the PREAMP GAIN db switch to the required gain setting. 5. If it is required that the source key the transceiver, connect EXT KEY IN on the transceiver to KEY OUT on the source. If it is required that the transceiver key the source, connect KEY OUT on the transceiver to KEY IN on the source. 6. Refer to "Setting Up the Channel 1 Bandpass Filter" below to configure the DSP-661 Processor Software for a source connected to Channel 1, or to "Setting Up the Channel 2 Bandpass Filter" on page 3-40 for a source connected to Channel 2. NOTE If the source is to trigger the transceiver, be sure to select External in the Trigger Source area of the Chirp 2 Controls window. System Manual September 1999

87 CAP-6600 Chirp II Acoustic Profiling System 3-39 Setting Up the Channel 1 Bandpass Filter Perform the steps listed below to configure the DSP-661 Processor Software for operation with a Bubble Pulser or other seismic source connected to Channel Refer to "Activating the DSP-661 Processor" on page 3-19 for instructions on how to turn on the processor and start the DSP-661 Processor Software. 2. Turn off the Channel 1 transmitter by using the Ch1 scroll bar in the Power Controls area of the Chirp 2 Controls window to set the Channel 1 transmitter attenuation to OFF. 3. Select Display from the menu bar, select Filter Type, and then choose Band Pass Filter Channel Select Tools from the menu bar, and then choose Filter. The Bandpass Filter Setup dialog box shown in Figure 3-19 opens. 5. In the Filter Type area of the Bandpass Filter Setup dialog box, select Band Pass. 6. In the Time Zero area use the scroll bar to select 5 (0.2ms). 7. In the Channel Select area select CH In the Filter Parameters area use the Low Cutoff Freq. and High Cutoff Freq. scroll bars to set the low and high cutoff frequencies of the filter. For a Bubble Pulser set the low cutoff frequency to 200 Hz and the high cutoff frequency to 600 Hz. 9. In the Rectifier area select Positive. Figure 3-19 The Bandpass Filter Setup Dialog Box 10. Click Set DSP Filter to save the settings, and then click Exit to close the Bandpass Filter Setup dialog box. SECTION 3 Setup and Deployment Other System Configurations

88 3-40 DATASONICS Setting Up the Channel 2 Bandpass Filter Perform the steps listed below to configure the DSP-661 Processor Software for operation with a Bubble Pulser or other seismic source connected to Channel Refer to "Activating the DSP-661 Processor" on page 3-19 for instructions on how to turn on the processor and start the DSP-661 Processor Software. 2. Turn off the Channel 2 transmitter by using the Ch2 scroll bar in the Power Controls area of the Chirp 2 Controls window to set the Channel 1 transmitter attenuation to OFF. 3. Select Display from the menu bar, select Filter Type, and then choose Band Pass Filter Channel Select Tools from the menu bar, and then choose Filter. The Bandpass Filter Setup dialog box shown in Figure 3-19 on page 3-39 opens. 5. In the Filter Type area of the Bandpass Filter Setup dialog box, select Band Pass. 6. In the Time Zero area use the scroll bar to select 5 (0.2ms). 7. In the Channel Select area select CH In the Filter Parameters area use the Low Cutoff Freq. and High Cutoff Freq. scroll bars to set the low and high cutoff frequencies of the filter. For a Bubble Pulser set the low cutoff frequency to 200 Hz and the high cutoff frequency to 600 Hz. 9. In the Rectifier area select Positive. 10. Click Set DSP Filter to save the settings, and then click Exit to close the Bandpass Filter Setup dialog box. Connecting a Heave Compensator Perform the steps listed below to connect a heave compensator. 1. Connect KEY OUT on the DSP-662 Transceiver to KEY IN on the heave compensator. 2. Connect KEY OUT on the heave compensator to DELAY KEY IN on the transceiver. 3. Switch the DELAY KEY IN switch on the transceiver to ON. System Manual September 1999

89 CAP-6600 Chirp II Acoustic Profiling System 4-1 SECTION 4 Operation SECTION 4 Operation

90 4-2 DATASONICS System Manual September 1999

91 CAP-6600 Chirp II Acoustic Profiling System 4-3 O nce the tow vehicle has been deployed and is stable and operating correctly, the tow vehicle can be lowered to depth and the recording of data can begin. Before beginning the recording of data, however, the control settings that were initially configured prior to the predeployment checks described in SECTION 3, "Setup and Deployment," may require reconfiguring. There are three main sets of control settings: the transmit and receive controls, which affect both the displayed and recorded data; the display gain and threshold controls, which affect only the displayed data; and the bottom tracking and time varied gain (TVG) controls, which also affect only the displayed data. In addition, the recording parameter settings, which include the recording data rate, the file format and the recording medium may have to be reconfigured, depending on the survey requirements. When all of the settings have been configured accordingly, the recording of data can begin. This section provides a general description of the control and recording parameter settings that are critical to the operation of the CAP-6600 Chirp II Acoustic Profiling System and how to use them effectively. In addition, procedures for formatting a magneto-optical disk and recording the data are included. NOTE Refer to the DSP-661 Processor Software Manual for more information on the operation of the software and on the many displays and controls provided. Control Settings Before beginning the recording of data, some control settings may need to be reconfigured from those set prior to the predeployment checks. They include the transmit and receive control settings, the display gain and threshold settings, and the bottom tracking and TVG control settings. The transmit and receive settings and the bottom tracking and TVG settings are entered in the Chirp 2 Controls window shown in Figure 3-14 on page The display gain and threshold settings are entered in the Display Gain Setup dialog box shown in Figure 3-12 on page If the Chirp 2 Controls window is not already open, refer to "Activating the DSP-661 Processor" on page 3-19 for instructions on how to turn on the processor and start the DSP-661 Processor Software. When the software is started, the Main and Chirp 2 Controls windows open as shown in Figure 3-7 on page SECTION 4 Operation Control Settings

92 4-4 DATASONICS Transmit and Receive The transmit and receive control settings are configured in the Controls section of the Chirp 2 Controls window. Trigger Source The trigger source is selected with option buttons in the Trigger Source area of the Controls section of the Chirp 2 Controls window. The trigger source option buttons and their descriptions are the following: Option Button Internal: External: Description When selected, the transceiver is keyed from the processor. When selected, the transceiver is keyed from an external source that is connected to EXT KEY IN of the transceiver. Transmit Repetition Rate The transmit repetition rate of both the Channel 1 and Channel 2 transmitters is controlled with a scroll bar in the Controls section of the Chirp 2 Controls window. The repetition rate control and its description is the following: Control Trig Rate: Description Sets the transmit repetition rate of the transmitters. The available repetition rates are 0.125, 0.25, 0.50, 1.00, 2.00, 4.00, and 8.00 seconds. The determination of the transmit repetition rate is based on the survey requirements and must consider the towing speed and altitude of the tow vehicle. Use of the fastest repetition rate for a given tow vehicle altitude will provide the maximum spacial resolution. For high altitude applications, refer to the DSP-661 Processor Software Manual for instructions on using multiping correction, which allows a high repetition rate to be used with the tow vehicle at a high altitude. Refer to Table 4-1 for the maximum tow vehicle altitude for each of the available repetition rates without multi-ping correction. NOTE The transmit repetition rate cannot be changed while recording data. System Manual September 1999

93 CAP-6600 Chirp II Acoustic Profiling System 4-5 Table 4-1 Transmit Repetition Rate vs. Maximum Tow Vehicle Altitude Transmit Repetition Rate (seconds) Maximum Tow Vehicle Altitude Without Multi-Ping Correction (meters) Chirp Pulse Length The Chirp pulse length is controlled with scroll bars in the Chirp Length area of the Controls section of the Chirp 2 Controls window. The Chirp pulse length controls and their descriptions are the following: Control Ch1: Ch2: Description Adjusts the Channel 1 Chirp pulse length from 5 to 50 msec. The available settings are 5, 10, 20, 30, 40 and 50 msec. Adjusts the Channel 2 Chirp pulse length from 5 to 50 msec. The available settings are 5, 10, 20, 30, 40 and 50 msec. In general, use short Chirp pulse lengths in shallow water or at low tow vehicle altitudes and longer pulse lengths when towing in deep water at high tow vehicle altitudes. NOTE Adjusting either the Ch1 or the Ch2 scroll bar sets the Chirp pulse lengths for both channels to the same setting; i.e., the settings cannot be different for both channels. Click SET after adjusting the Chirp pulse length. The tow vehicle will begin transmitting at the set transmit repetition rate and Chirp pulse length. SECTION 4 Operation Control Settings

94 4-6 DATASONICS When Internal is selected for the trigger source, the system automatically limits the combination of the transmit repetition rate and the Chirp pulse length such that the transmit duty cycle does not exceed 15%. A warning message will be displayed if an attempt is made to exceed this limit. WARNING When External is selected for the trigger source, the system will neither limit nor warn of a transmit duty cycle that is too long. DO NOT use a transmit repetition rate and transmit pulse length that exceeds a 15% transmit duty cycle. The transmit duty cycle is calculated using the following formula: transmit duty cycle = pings per second x Chirp pulse length x 100% where pings per second is the reciprocal of the transmit repetition rate and Chirp pulse length is in seconds. For example, if the transmit repetition rate is set to 0.125, then pings per second is: pings per second = 1/0.125 or 8. And if the Chirp pulse length is 40 msec, then the duty cycle is: transmit duty cycle = 8 x x 100 or 32%. To reduce the transmit duty cycle to 15% or less, decrease the number of pings per second, decrease the Chirp pulse length, or both. Reducing the transmit repetition rate to 0.25 and the Chirp pulse length to 30 msec reduces the duty cycle to an acceptable 12%. Receiver Gain The Channel 1 and Channel 2 receiver gains are controlled with scroll bars in the Hardware Gain area of the Controls section of the Chirp 2 Controls window. The receiver gain controls and their descriptions are the following: Control Description Ch1: Adjusts the gain of the Channel 1 receiver from 0 to 42 db in 3 db increments. Ch2: Adjusts the gain of the Channel 2 receiver from 0 to 42 db in 3 db increments. System Manual September 1999

95 CAP-6600 Chirp II Acoustic Profiling System 4-7 Use the system default setting of 0 db for both channels until the transmit power has been set as described in "Transmitter Power" below. The AMP button is used with an external amplifier, which is used to add gain in a hull mount system. Transmitter Power The output power of the Channel 1 and Channel 2 transmitters is controlled with scroll bars in the Power Controls area of the Controls section of the Chirp 2 Controls window. The transmitter controls and their descriptions are the following: Control Description Ch1: Adjusts the power of the Channel 1 transmitter from 0 to 21 db of attenuation, and OFF, in 3 db increments. Ch2: Adjusts the power of the Channel 2 transmitter from 0 to 21 db of attenuation, and OFF, in 3 db increments. NOTE The Display Threshold settings in the Display Gain Setup dialog box should be initially set to 4. Refer to "Display Gain and Threshold" below. When acquiring and processing profile data, adjust the transmit power for each channel while observing the bottom tracking displays, which are located on the right side of the Profile - CH1+CH2 window. The traces should be at 40% to 50% of full scale and should never clip; i.e., they should not flatten out against the right side of the display. In addition, the first return, which is shown at the top of the display, should be at least 50% of full scale. If these levels cannot be attained, then adjust the receiver gain, which is described in "Receiver Gain" on page 4-6, to bring the displayed signal to the correct level. Display Gain and Threshold The display gain amplifies the weaker return signals more than the stronger signals to enhance sediment details. The display threshold sets the amount of information displayed. Neither the display gain nor the display threshold affect the recorded data. The display gain and threshold settings are entered in the Display Gain Setup dialog box shown in Figure 3-12 on page SECTION 4 Operation Control Settings

96 4-8 DATASONICS NOTE Spreading loss correction is recorded as well as displayed. Refer to the DSP-661 Processor Software Manual for more information. To open the Display Gain Setup dialog box, select Display from the menu bar, and then choose Display Gain. The display gain is controlled with a scroll bar in the Display Gain area of the Display Gain Setup dialog box. The display gain control and its description is the following: Control Current Gain: Description Adjusts the display gain. The range is from 0 to 49 db, where 0 db is linear. NOTE Increasing the display gain also amplifies noise in the return signals. The display threshold is controlled with scroll bars in the Display Threshold area of the Display Gain Setup dialog box. The display threshold controls and their descriptions are the following: Control CH 1: CH 2: Description Adjusts the Channel 1 display threshold. The range is from 1 to 8. Adjusts the Channel 2 display threshold. The range is from 1 to 8. Click anywhere in the Profile - CH1+CH2 window to make it active. Adjust the display gain for the desired display. The recommended setting is between 9 db and 22 db. Then adjust the display thresholds so that the traces in the bottom tracking displays, which are located on the right side of the Profile - CH1+CH2 window, do not clip; i.e., they do not flatten out against the right side of the display. The recommended settings for both Channel 1 and Channel 2 is 4. After adjusting the display gain and display threshold settings, click OK to save the settings and close the Display Gain Setup dialog box. System Manual September 1999

97 CAP-6600 Chirp II Acoustic Profiling System 4-9 Bottom Tracking and TVG For the optimum display of profile data it is important to understand both the automatic and manual bottom tracking features of the system and how they function with the time varied gain (TVG) that is applied to the sonar signals. This is important in order to acquire and maintain the correct tow vehicle altitude while avoiding an accidental collision with the bottom. Automatic bottom tracking continuously monitors the tow vehicle s height off the bottom. This altitude information is used to acquire bathymetry data and to provide a starting point for the TVG. The level of TVG that is applied to the received sonar signals is important in order to enhance imagery from the deep subbottom layers. The TVG is entirely operator adjustable, affects only the display, and is not recorded. The TVG does not begin until the automatic bottom tracking has detected the bottom. Manual bottom tracking allows the operator to specify the altitude of the vehicle, hence the start of the TVG. NOTE If Manual is selected for bottom tracking, the TVG begins at a fixed depth. This depth is controlled with the Holdoff setting, which is described on page Automatic or manual bottom tracking is selected with option buttons in the Bottom Tracking-TVG section of the Chirp 2 Controls window. The automatic and manual bottom tracking option buttons and their descriptions are the following: Option Button Auto: Manual: Description When selected, the bottom tracking function is performed automatically. When selected, the bottom tracking function is performed manually. The bottom tracking channel for automatic bottom tracking is selected with option buttons that are in the Track Channel area of the Bottom Tracking-TVG section of the Chirp 2 Controls window. The automatic bottom tracking channel option buttons and their descriptions are the following: SECTION 4 Operation Control Settings

98 4-10 DATASONICS Option Button Ch 1: Ch 2: Description When selected, Channel 1 performs the automatic bottom tracking function if Auto is selected for bottom tracking. When selected, Channel 2 performs the automatic bottom tracking function if Auto is selected for bottom tracking. The automatic and manual bottom tracking and the TVG are controlled with scroll bars in the Bottom Tracking-TVG section of the Chirp 2 Controls window. The automatic and manual bottom tracking and TVG controls and their descriptions are the following: Control Track Sensitivity: Holdoff: TVG Ch 1: Description Adjusts the amplitude threshold at which a received signal will be detected as the bottom. This control is active only if Auto is selected for bottom tracking. The range is from 1% to 90% of the amplitude range of the received signals. Adjusts the depth at which the auto bottom tracking will begin to look for the bottom if Auto is selected for bottom tracking. If Manual is selected, then it adjusts the depth at which the TVG begins. The range is from 0 to full scale, in 1 meter increments, as determined by the transmit repetition rate setting in the Recording Data Rate dialog box. Adjusts the TVG for Channel 1. The TVG begins when the auto bottom tracking detects the bottom or at the fixed depth selected with the Holdoff control. The range is from 0 to 6 db/m in 0.01 db/m increments. The maximum gain is 30 db. System Manual September 1999

99 CAP-6600 Chirp II Acoustic Profiling System 4-11 TVG Ch 2: Smooth: Adjusts the TVG for Channel 2. The TVG begins when the auto bottom tracking detects the bottom or at the fixed depth selected with the Holdoff control. The range is from 0 to 6 db/m in 0.01 db/m increments. The maximum gain is 30 db. Filters the tow vehicle altitude measurement to reduce the effects of tow vehicle heave. This control is active only when Auto is selected for bottom tracking. The range is from 0% to 97%. NOTE Smoothing will also filter out periodic bottom changes and should be used primarily when the bottom is relatively flat or if small periodic bottom changes are not important. RESET sets the Sensitivity to 15%, bottom tracking to Auto, and Holdoff to 0. If auto bottom tracking is to be used, select either Channel 1 or Channel 2 for the bottom tracking channel. Channel 1 is the system default selection and is the low frequency channel. Channel 1 should be used particularly if there is suspended sediment throughout the water column. Select Channel 2, which is the high frequency channel, if the bottom is soft or there is a significant amount of suspended sediment just near the bottom. Adjust the Sensitivity control to between 35% and 50%, and then adjust the TVG for each channel for the desired display. NOTE It may be necessary to adjust the Holdoff such that the auto bottom tracking does not detect the outgoing pulse. The Holdoff can also be adjusted to eliminate false bottom tracking due to noise in the water column. WARNING Never set Holdoff to a value that is equal to or greater than the tow vehicle s altitude. A Holdoff setting that is too high could cause the tow vehicle to appear to be at a higher altitude than it actually is, hence risking a collision with the bottom. SECTION 4 Operation Control Settings

100 4-12 DATASONICS Recording Parameter Settings If data are to be recorded during the survey, the recording parameter settings should be reviewed prior to lowering the tow vehicle to depth. These settings were originally configured prior to activating the tow vehicle and performing the predeployment checks. For depending on the data storage requirements of the survey, these settings may need to be reconfigured. The settings are made in the Recording Data Rate dialog box shown in Figure 3-10 on page To open the Recording Data Rate dialog box, select File from the menu bar, and then choose Record. The Record Setup dialog box shown in Figure 3-9 on page 3-22 opens. In the Record Setup dialog box, click Display and Record. The Recording Data Rate dialog box opens. Recording Data Rate The recording data rate is entered in the Recording Data Rate dialog box. The recording data rate is the number of samples per ping to be recorded for each channel. This is limited, in part, by the number of samples per second that can be recorded, which is 15,000. The default or the user defined recording data rate is selected with check boxes in the Recording Data Rate dialog box. The check boxes and their descriptions are the following: Check Box Default: User Define: Description When selected, the maximum recording data rate is set automatically for the set transmit repetition rate. When selected, the recommended recording data rate is set automatically for the set transmit repetition rate, or a user defined recording data rate may be entered. NOTE The User Define check box is selected by default when the Recording Data Rate dialog box is initially opened after system startup. In addition, the recommended recording data rate will be selected automatically for the set transmit repetition rate. System Manual September 1999

101 CAP-6600 Chirp II Acoustic Profiling System 4-13 The recording data rate is selected with option buttons in the User Define Data Rate area of the Recording Data Rate dialog box. The recording data rate option buttons and their descriptions are the following: Option Buttons Description 1024: Records 1024 samples for each ping. 2048: Records 2048 samples for each ping. 4096: Records 4096 samples for each ping. 8192: Records 8192 samples for each ping. In addition, if the User Define check box is selected, the User Define text box can be used to enter a specific data rate. Refer to Table 4-2 for the recommended recording data rate for the set transmit repetition rate. NOTE A warning message will be displayed if a recording data rate that exceeds 15,000 samples per second is selected. If the User Define check box is selected, select or enter the highest recording data rate allowable for the set transmit repetition rate if it is desired to record the most data. The highest recording data rate, or samples per ping, allowable for the set transmit repetition rate is calculated using the following formula: maximum samples per ping = 15000/pings per second Where pings per second is the reciprocal of the transmit repetition rate. For example, if the repetition rate is set to 0.25, then pings per second is: pings per second = 1/0.25 or 4. Therefore, the maximum samples per ping is: maximum samples per ping = 15000/4 or 3750, which can be entered in the User Define text box. NOTE The maximum number of samples per ping is limited to For deep water with the tow vehicle at a high altitude, multi-ping correction can be used instead of a slow repetition rate. Refer to the DSP-661 Processor Software Manual for instructions on how to use multi-ping correction. SECTION 4 Operation Recording Parameter Settings

102 4-14 DATASONICS Table 4-2 Recommended Recording Data Rate Transmit Repetition Rate (seconds) Recording Data Rate Recording File Format The recording file format is selected with option buttons in the Recording Format area of the Recording Data Rate dialog box. The recording format option buttons and their descriptions are the following: Option Button Q-MIPS: SEG-Y: Description Records in the Q-MIPS format. Records in the SEG-Y format. NOTE The Q-MIPS file format is not used with the CAP-6600 Chirp II Acoustic Profiling System. System Manual September 1999

103 CAP-6600 Chirp II Acoustic Profiling System 4-15 Recording Time Calculations If the recording data rate, the transmit repetition rate and the size of the recording medium are known, the total recording time in hours for the recording medium can be calculated. First, the bytes recorded per ping (BPP) must be calculated. To calculate BPP use the following formula: Where NCR = Number of channels to record two SPC = Recording data rate samples per ping BPX = BPP = NCR SPC BPX Sample size to record 16 bits per pixel and 256 is a fixed number of bytes. Next, now that BPP is known, the bytes per second to record (BPS) can be calculated from the known transmit repetition rate (TRR). To calculate BPS use the following formula: BPS = BPP TRR The total recording time in hours (TRT) can now be calculated using the following formula: TMC TRT = BPS 3600 Where TMC is the total medium capacity in bytes and 3600 converts seconds to hours. For example, if 2 channels are to be recorded at a recording data rate of 2048 samples per ping with a sample size to record of 16 bits per pixel, then SECTION 4 Operation Recording Parameter Settings

104 4-16 DATASONICS 16 BPP = = 8448 bytes per ping. And for a transmit repetition rate of seconds, BPS = 8448 = bytes per second. Hence the approximate total recording time in hours for a 2.2 GB magneto-optical disk is TRT = = 18.1 hours, or approximately 9 hours per side. Formatting a Magneto-Optical Disk If a magneto-optical disk will be used as the storage medium, the disk will require formatting before any data can be recorded on it. Perform the steps listed below to format a magneto-optical disk. If the DSP-661 Processor is not turned on, first perform Step 1 through Step 3 in "Activating the DSP-661 Processor" on page 3-19 to go to the Windows desktop. 1. Insert the magneto-optical disk into the magneto-optical drive. 2. Click Start to open the Start menu, and then choose Programs to open the Programs menu. 3. Choose Windows Explorer from the Programs menu. Windows Explorer opens. 4. In Windows Explorer look for "Removable Disk (E:)," which is the magneto-optical drive. Although the drive letter is typically E, a different drive letter may be assigned, depending on the number of storage devices installed. System Manual September 1999

105 CAP-6600 Chirp II Acoustic Profiling System Using the right trackball button, click "Removable Disk (E:)," and then choose Format from the pop-up menu that opens. The Format - Removable Disk dialog box shown in Figure 4-1 opens. Figure 4-1 The Format - Removable Disk Dialog Box 6. In the Format type area of the Format - Removable Disk dialog box, select Full. 7. In the Other options area select Display summary when finished. 8. Click Start. A Format - Removable Disk message window opens warning that formatting will destroy all existing files on the disk: 9. Click OK. SECTION 4 Operation Formatting a Magneto-Optical Disk

106 4-18 DATASONICS The formatting process begins and a progress indicator opens at the bottom of the Format - Removable Disk dialog box. When the formatting is complete, the Format Results - Removable Disk dialog box shown in Figure 4-2 opens. Figure 4-2 The Format Results - Removable Disk Dialog Box 10. Verify that the information shown in the Format Results - Removable Disk dialog box indicates the disk has been formatted correctly, and then click close to close the dialog box. A Format - Removable Disk information window opens informing that Windows has formatted the disk: 11. Click OK. One side of the magneto-optical disk is now formatted. To format the other side, remove the disk, turn it over, reinsert it into the magneto-optical drive, and then repeat the entire disk formatting procedure. System Manual September 1999

107 CAP-6600 Chirp II Acoustic Profiling System 4-19 Recording Data Once the desired tow vehicle altitude is attained, the recording of data can begin. Perform the steps listed below to begin recording data. 1. Select File from the menu bar, and then choose Record. The Record Setup dialog box shown in Figure 3-9 on page 3-22 opens. 2. In the Record Setup dialog box, click Display and Record. The Recording Data Rate dialog box shown in Figure 3-10 on page 3-22 opens. 3. Check the Default or the User Define check box. If the User Define check box is checked, select a recording data rate in the User Define Data Rate area of the Recording Data Rate dialog box, or enter one in the User Define text box. 4. In the Recording File Format area select SEG-Y. 5. Click OK to save the settings and close the Recording Data Rate dialog box. The Record/Playback dialog box shown in Figure 4-3 opens. Figure 4-3 The Record/Playback Dialog Box SECTION 4 Operation Recording Data

108 4-20 DATASONICS 6. In the Record Medium Select area of the Record/Playback dialog box, click the Disk icon. The Save As dialog box shown in Figure 4-4 opens. Figure 4-4 The Save As Dialog Box 7. Click the arrow in the Save in drop-down list box and select the folder in which to save the data file. 8. In the File name text box enter the name of the file in which to save the data. The extension.seg is added automatically. 9. Click Save. The message "DSP Loading... Please Wait..." is displayed for a few seconds. If it is the first time the DSP-661 Processor Software has been started, the default display setup consisting of the Profile - CH1+CH2 window opens as shown in Figure 3-11 on page 3-23, and profile data are displayed. After a short time, and only if navigation data are not available, or if a shipboard navigation system is not connected to the NAV connector of the DSP-661 Processor, the Chirp 2 Navigation Warning dialog box opens with a message warning that there is no navigation data: System Manual September 1999

109 CAP-6600 Chirp II Acoustic Profiling System 4-21 Click OK to close the Chirp 2 Navigation Warning dialog box. This dialog box will appear every two minutes until there is navigation data or the Nav ON check box is cleared in the Communication Port Setup dialog box. Refer to "Configuring the Navigation Parameters" on page 3-20 for instructions on how to open the Communication Port Setup dialog box. SECTION 4 Operation Recording Data

110 4-22 DATASONICS System Manual September 1999

111 CAP-6600 Chirp II Acoustic Profiling System 5-1 SECTION 5 Theory of Operation SECTION 5 Theory of Operation

112 5-2 DATASONICS System Manual September 1999

113 CAP-6600 Chirp II Acoustic Profiling System 5-3 A n overall understanding of how the CAP-6600 Chirp II Acoustic Profiling System produces the high resolution sonar images is an important factor in ensuring that the system is properly maintained and that its maximum performance is realized. This section provides an overall description of the CAP-6600 Chirp II Workstation signal flows and processing, from the generation of the transmit signals to the acquisition and processing of the received signals. Beginning with an overall functional description using block diagrams, the circuit functions and signal flows are identified. This is followed by a detailed description of the signal processing at the printed circuit board level. Refer to SECTION 7, "Drawings," for the block diagrams, assembly drawings, and schematics called out in this section. Functional Description The CAP-6600 Chirp II Workstation hardware is composed of two major functional components: the DSP-661 Processor and the DSP-662 Transceiver. A block diagram that portrays the processor and the transceiver main functional components is shown in Drawing B The processor and transceiver wiring diagrams are shown in Drawings B and D , respectively. Processor Along with the high resolution monitor, the keyboard, and the trackball, the DSP-661 Processor includes several other functions: the host CPU with a Pentium based processor that provides the serial communications ports COM1 and COM2, and the parallel ports LPT1 and LPT2; the SCSI interface, which connects to the hard drive and the optional high-density storage devices; the graphics processor, which drives the high resolution monitor; the two digital signal processors, which process the received subbottom signals; and the Burst/Receiver board, which generates the Chirp transmit waveforms and receives the subbottom signals. The processor is powered from a VAC or VAC, Hz power source and interfaces with the transceiver through a single multi-conductor cable. The Pentium based CPU, which runs the DSP-661 Processor Software, inputs navigation data on the COM1 serial port. The COM2 serial port connects to the trackball, the LPT1 parallel port connects to an optional printer, and the LPT2 parallel port connects to the Remote Controlled Transmit/Receive Module in a hull mount system. The SCSI interface services up to seven internal or external devices, including the installed hard drive and the magneto-optical drive. SECTION 5 Theory of Operation Functional Description

114 5-4 DATASONICS The graphics processor provides a resolution for the monitor of 1280 x 1024 in 256-color mode. The two digital signal processors and the Burst/Receiver board are connected to the ISA bus of the processor. The digital signal processors perform the match-filter processing of the received subbottom signals that are input from the Burst/Receiver board. The processed data is then output to the CPU on the ISA buss. In addition, both the Channel 1 and Channel 2 matched-filtered analog data is output to the Burst/Receiver board and then output to the front panel of the transceiver. The Burst/Receiver board performs four primary functions: the generation of the Chirp transmit waveforms, diagnostic signals, and transmit gates for both the Channel 1 and Channel 2 transmitters; receives an external key and provides the system key to trigger the Channel 1 and Channel 2 transmitters or an alternate source or both; provides the power level controls for the Power Amplifier boards; and it receives and amplifies the filtered hydrophone array or transducer output from the transceiver. Transceiver The DSP-662 Transceiver amplifies the Channel 1 and Channel 2 Chirp transmit waveforms that are input from the Burst/Receiver board in the processor and filters the hydrophone array or transducer output. The transceiver also includes a preamplifier with adjustable gain for amplifying the output of a Bubble Pulser hydrophone array or an alternate non-chirp source before it is input to one of the analog input channels of the transceiver. In addition, a Transmit/Receive (T/R) network is incorporated which allows the transceiver to both transmit and receive from the same transducer. The main functional components of the transceiver are the circuit boards, all of which are located in the transceiver chassis shown in Figure 5-1. The circuit boards include the Front Panel Distribution board, the Rear Panel Distribution board, the Power Amplifier boards, and the Transformer Jumper boards. The Front Panel Distribution board performs four primary functions: the distribution of signals both from the Burst/Receiver board in the processor to the Power Amplifier boards and from the Rear Panel Distribution board to the Burst/Receiver board; the distribution of DC power to the Power Amplifier boards and the Rear Panel Distribution board; the preamplification of the hydrophone array or transducer output; and the interfacing with the operator functions and connectors on the transceiver front panel. When keyed by the Burst/Receiver board in the processor, the Front Panel Distribution board outputs the Chirp transmit waveform and transmit gate, which are both input System Manual September 1999

115 SECTION 5 Theory of Operation Functional Description REAR PANEL DISTRIBUTION BOARD HIGHPASS FILTER FL2 BANDPASS FILTER FL1 CHASSIS SCREWS (4) (REMOVE TO REMOVE ELECTRONICS CHASSIS) POWER AMPLIFIER BOARD (CHANNEL 2) ELECTRONICS CHASSIS REMOVAL HANDLES (2) TRANSFORMER JUMPER BOARD (CHANNEL 2) TRANSFORMER T1 (CHANNEL 2) COOLING FAN CONTROL LOGIC CONNECTOR CHANNEL 2 ENERGY STORAGE CAPACITORS (UNDER POWER AMPLIFIER AND TRANSFORMER JUMPER BOARDS) AC LINE FILTER TRANSDUCER CONNECTOR NOTE: A POWER AMPLIFIER BOARD, A TRANSFORMER JUMPER BOARD, AND AN ENERGY STORAGE CAPACITOR BANK ARE A SINGLE REMOVABLE MODULE, ONE MODULE FOR EACH CHANNEL. TO REMOVE A MODULE, DISCONNECT THE CABLES AND REMOVE THE FOUR MOUNTING SCREWS. Figure 5-1 Transceiver Chassis BPR CONNECTOR +/-12 VDC POWER SUPPLY +48 VDC POWER SUPPLY POWER AMPLIFIER BOARD (CHANNEL 1) TRANSFORMER JUMPER BOARD (CHANNEL 1) TRANSFORMER T1 (CHANNEL 1) FRONT PANEL DISTRIBUTION BOARD CHANNEL 1 ENERGY STORAGE CAPACITORS (UNDER POWER AMPLIFIER AND TRANSFORMER JUMPER BOARDS) CAP-6600 Chirp II Acoustic Profiling System 5-5

116 5-6 DATASONICS from the Burst/Receiver board, to each of the Power Amplifier boards. In addition, separate power level controls, which also are input to the Front Panel Distribution board from the Burst/Receiver board, are output to the Power Amplifier boards. The Channel 1 and Channel 2 received signals are input to the Front Panel Distribution board from the Rear Panel Distribution board, and then output to the Burst/Receiver board. The DC power is input to the Front Panel Distribution board from the power supplies, and then output to the Power Amplifier boards and the Rear Panel Distribution board. The preamplifier on the Front Panel Distribution board applies 0, 15, or 30 db of gain to a signal that is applied to the PREAMP IN input. The output of the preamplifier is applied to the PREAMP OUT output. All the transceiver front panel operator functions, which include the switches and indicators as described in "Transceiver Operator Functions" on page 3-17, connect to the Front Panel Distribution board. In addition, all the transceiver front panel connectors as described in "Transceiver Front and Rear Panel Connections" on page 3-11, connect to the Front Panel Distribution board. The Rear Panel Distribution board performs three primary functions: the distribution of power to the hydrophone array preamplifiers and amplified Chirp transmit waveforms to the transducers; the filtering of the received signals from the hydrophone arrays or transducers; and the interfacing with the operator functions and connectors on the transceiver rear panel. DC power that is input to the Rear Panel Distribution board from the Front Panel Distribution board is output to the Bubble Pulser and Chirp hydrophone array preamplifiers. Both the Channel 1 and Channel 2 amplified Chirp transmit waveforms are input to the Rear Panel Distribution board from the Power Amplifier boards and then output to the transducers. The hydrophone and transducer outputs are input directly to the Rear Panel Distribution board. If transducers are used to both transmit and receive the sonar signals, the CH1 HYDROPHONE/T/R switch or the CH2 HYDROPHONE/T/R switch or both are switched to T/R and the transducer outputs from the T/R network on the Power Amplifier board are input to the Rear Panel Distribution board. The hydrophone array and transducer output signals are filtered to separate the Channel 1 low frequency signals from the Channel 2 high frequency signals, and then output to the Front Panel Distribution board. All the transceiver rear panel operator functions, which include the switches as described in "Transceiver Operator Functions" on page 3-17, connect to the Rear Panel Distribution board. In addition, with the exception of CONTROL LOGIC, all the transceiver rear panel connectors as described in "Transceiver Front and Rear Panel Connections" on page 3-11, connect to the Rear Panel Distribution board. System Manual September 1999

117 CAP-6600 Chirp II Acoustic Profiling System 5-7 The Power Amplifier boards amplify the Chirp transmit waveforms that are input from the Front Panel Distribution board and drive the transducers. The transmit power level control input from the Front Panel Distribution board sets each of the transmitter s output power level. In addition the Power Amplifier boards each incorporate a T/R network that allows the system to transmit and receive from the same transducers. The T/R network also preamplifies the subbottom return signals. The Transformer Jumper boards function with the Power Amplifier boards and allow jumper selection of different power levels. Each Transformer Jumper board includes a single multi-tapped transformer with a choice of seven available output power levels. Circuit Board Description The circuit board description encompasses the boards that perform the functions described for the DSP-661 Processor and the DSP-662 Transceiver. Processor Circuit Boards Listed below are the circuit boards in the block diagram shown in Drawing B Included are the corresponding schematic and assembly drawings. Circuit Board Schematic Drawing Assembly Drawing DSP: (OEM supplied) (OEM supplied) Burst/Receiver: D D DSP Board There are two DSP boards in the processor. They are Original Equipment Manufacturer (OEM) supplied. If required, contact technical support at Datasonics for more information on the DSP boards. For information on the configuration of the DSP boards, including jumper settings and selectable components, refer to Drawing A SECTION 5 Theory of Operation Circuit Board Description

118 5-8 DATASONICS Burst/Receiver Board The Burst/Receiver board interfaces with the CPU and the DSP boards through the ISA buss and connects to the transceiver through the CONTROL LOGIC connector on the back of the processor. In the burst control section of the Burst/Receiver board, 16-bit Channel 1 and Channel 2 Chirp transmit waveform information for a given Chirp pulse length is loaded into FIFO memory U16-U19 from the CPU under software control. At the start of each ping cycle, an internal or external key pulse sets flip-flops U20A and U20B, whose Q outputs are the Channel 1 and Channel 2 transmit gates, respectively, which are output on J12. The transmit gates also enable flip-flops U22A and U21B, whose clock frequency is input on pins 3 and 11, respectively, from U14, pin 9. The Q outputs of U22A and U21B, which are half the input clock frequency, are input to nand gates U31C and U5D, whose outputs increment the addresses of U16-U19. For each incremented address the 12-bit output of U16 and U17 is input to the Channel 1 D/A converter U23, and the 12-bit output of U18 and U19 is input to the Channel 2 D/A converter U24. The addresses of U16-U19 are continuously incremented at the clock rate, and the contents of the addresses are output to the D/A converters for the entire pulse length. The contents of the last address loaded into U16-U19 from the CPU has bit 15 set. When this address is clocked, Q7 of U16 and Q7 of U19 reset flip-flops U20A and U20B through nor gates U26A and U26B, respectively. The 12-bit inputs to the D/A converters are converted to analog voltages at the same clock rate used to increment the addresses of U16-U19. The output of the Channel 1 D/A converter is input to the signal conditioning circuit composed of U25A, U25B, and U29A, and the output of the Channel 2 D/A converter is input to the signal conditioning circuit composed of U27A, U27B, and U29B. Each signal conditioning circuit first filters and then zero crossing detects the signals, producing a square wave output at U29A, pin 1 and U29B, pin 2. The outputs of the signal conditioning circuits are input to analog switches U53B and U53A, which output the signals on J12, if the system is running in normal mode, or output the signals to the receivers in the receiver section of the Burst/Receiver board if the system is running in diagnostic mode. The internal key pulse is generated in the burst control section of the Burst/Receiver board using a base clock frequency of 32 Hz that is generated by the counter/oscillator composed of crystal Y1, inverters U10B and U10E, and counter U13. The clock frequency is output to programmable counter U12, which is set by the CPU under software control. The output of U12 is the internal key pulse, which is inverted by U10C and input to analog switch System Manual September 1999

119 CAP-6600 Chirp II Acoustic Profiling System 5-9 U33A, pin 18. The external key pulse, which is input on J12, is applied to analog switch U33A, pin 20. The analog switch is set by the CPU under software control and selects whether the internal or the external key will start a ping cycle. The output of the analog switch is differentiated with C93 and R74, and buffered with U6C to limit the pulse width to 100 µsec. The output of U6C is output on J12 and is buffered by U6D and U6B. The outputs of U6D and U6B are output on J6 and J7 to the Channel 1 and Channel 2 DSP boards, respectively. When the system is running in diagnostic mode, a diagnostic key pulse, whose repetition rate is four times that of the key pulse in the normal mode, is generated. The diagnostic key pulse is generated in the burst control section of the Burst/Receiver board by the oscillator/counter circuit composed of crystal Y1, inverters U10B and U10E, counter U13, and programmable counter U50. The output of U50 is the diagnostic key pulse, which is inverted by U59A and input to analog switches U57B and U57A. The analog switches are set by the CPU under software control. When in the diagnostic mode, the output of each switch is the diagnostic key pulse, which sets flip-flops U20A and U20B and generates Chirp transmit waveforms four times during each ping cycle. The Chirp transmit waveforms are output to analog switches U53B and U53A, and then to analog switches U52A and U52B. The outputs of U52A and U52B are input to the receivers in the receiver section of the Burst/Receiver board. The power-up default setting is the normal mode. The transmit power control signals are input to the Burst/Receiver board from the CPU under software control. The power control consists of three bits, which set eight different power level controls for the Power Amplifier boards in the transceiver. The control signals are latched into U30 and are output on J12. Two receivers in the receiver section of the Burst/Receiver board input the Channel 1 and Channel 2 filtered subbottom signals from the transceiver. The signals are input on J12 and applied to pin 18 of analog switch U52A and pin 16 of analog switch U52B. If the system is running in normal mode, the outputs on pins 19 and 14 are the signal inputs from the transceiver. If the system is running in diagnostic mode, the Chirp transmit waveforms for each channel are applied to pin 20 of U52A and pin 13 of U52B and are output on pins 19 and 14. The outputs of the analog switches are input to the active highpass filters composed of amplifiers U34 and U35 for Channel 1, and U39 and U40 for Channel 2. The output of the high pass filters are input to programmable gain circuits composed of U36 and U37, and U41 and U42. SECTION 5 Theory of Operation Circuit Board Description

120 5-10 DATASONICS The gains of the programmable gain circuits are set by the CPU under software control. The outputs of the programmable gain circuits are input to active lowpass filters U38 and U43. The outputs of the lowpass filters are input to analog switches U60A and U60B. In addition, using mixers U63 and U50, the outputs of the low pass filters are mixed with a local oscillator, which is composed of crystal Y2, crystal controlled counter U48, programmable counter U46, and phase-lock-loop U47. The frequency of the local oscillator is set with switch S2. The output of the phase-lock-loop is lowpass filtered with U49 and then input to the mixers. The outputs of the mixers are lowpass filtered with U64 and U51 and then input to analog switches U60A and U60B. The analog switches, which are individually set by the CPU under software control, select whether the output for each channel is to be the mixed received signal or the unmixed received signal. The power-up default setting outputs unmixed received signals on Channel 1 and mixed received signals on Channel 2. The outputs of the analog switches are input to active lowpass anti-aliasing filters U61 and U56. The outputs of the anti-aliasing filters are output on J6 and J7 and input to the Channel 1 and Channel 2 DSP boards. Transceiver Circuit Boards Listed below are the circuit boards in the block diagram shown in Drawing B Included are the corresponding schematic drawings and assembly drawings. Refer to Figure 5-1 on page 5-5 for the location of the circuit boards and other components called out in the descriptions. Circuit Board Schematic Drawing Assembly Drawing Front Panel Distribution: C B Rear Panel Distribution: C B Power Amplifier: D C Transformer Jumper: B A Front Panel Distribution Board The Front Panel Distribution board connects to the processor through the CONTROL LOGIC connector on the back panel of the transceiver, and it interfaces with the Rear Panel Distribution board and the Power Amplifier boards in the transceiver. System Manual September 1999

121 CAP-6600 Chirp II Acoustic Profiling System 5-11 The Front Panel Distribution board is powered with +/-12 VDC and +48 VDC, which are input on J13. The +48 VDC drives red LED D3 through resistor R17 to verify operation of the +48 VDC power supply, and then it is output on J13 and input to both Power Amplifier boards. The +12 VDC drives red LED D1 through resistor R15 to verify operation of the +12 VDC power supply. The +12 VDC is filtered by L1, C2, and C3 and then input to the preamp section of the Front Panel Distribution board. The filtered +12 VDC is also output on J14 and input to the Rear Panel Distribution board. The -12 VDC drives red LED D2 through resistor R16 to verify operation of the -12 VDC power supply. The -12 VDC is filtered by L2, C4, and C5, and then it is output on J14 and input to the Rear Panel Distribution board. The Chirp transmit waveforms, the transmit gates, the power level control signals, and the internal key are all input on J12 from the Burst/Receiver board in the processor. The Chirp transmit waveforms, the transmit gates, and the power level control signals then are output on J13 to the Power Amplifier boards. The internal key and the analog outputs are input on J12 and output to the transceiver front panel. When switch S4 is switched to ON, the external and delay keys are input to the Front Panel Distribution board and then output on J12 to the Burst/Receiver board. Similarly, when switches S2 and S3 are switched to ON, the analog inputs are input to the Front Panel Distribution board and then output on J12 to the Burst/Receiver board. The filtered Channel 1 and Channel 2 subbottom signals are input on J14 and output on J12 when the switches S2 and S3 are switched to OFF. The Channel 1 and Channel 2 transmit gates are also used to drive the TRANSMIT CH1 LED and the TRANSMIT CH2 LED on the transceiver front panel. The LEDs connect to J15 on the Front Panel Distribution board. The Channel 1 transmit gate, LFGATE, is applied to the base of transistor Q1 through resistor R12. When the gate is a logic high during a transmit burst, Q1 turns on and the TRANSMIT CH1 LED lights. The Channel 2 transmit gate, HFGATE, is applied to the base of transistor Q1 through resistor R13. When the gate is a logic high during a transmit burst, Q2 turns on and the TRANSMIT CH1 LED lights. The POWER indicator LED on the transceiver front panel also connects to J15 on the Front Panel Distribution board. The LED lights when +12 VDC is applied through resister R14, which occurs when the POWER switch is turned on. The preamplifier on the Front Panel Distribution board inputs analog signals from the transceiver front panel and applies a fixed, selectable gain of 0, 15, or 30 db to the signals and outputs the amplified signals to the transceiver front panel. SECTION 5 Theory of Operation Circuit Board Description

122 5-12 DATASONICS Rear Panel Distribution Board The Rear Panel Distribution board interfaces with the Front Panel Distribution board and the Power Amplifier boards. The Rear Panel Distribution board also connects to the Bubble Pulser and the hydrophone array or transducers through the BPR and TRANSDUCER connectors, respectively, on the back panel of the transceiver. The Rear Panel Distribution board inputs +/-12 VDC on J2 from the Front Panel Distribution board and outputs +/-12 VDC on J1 to power both the Bubble Pulser and Chirp hydrophone arrays. Received signals from the Chirp hydrophone array connected to TRANSDUCER are input on J1, output to switches S2 and S3, and then output to the transceiver rear panel. Received signals from the Bubble Pulser hydrophone array connected to BPR are input on J1 and output on J2. Both the Channel 1 and Channel 2 amplified transmit signals are input on J3 and output on J1. The Channel 1 and Channel 2 T/R received signals are input on J3. The Channel 1 T/R received signals connect to switch S3, and the Channel 2 T/R received signals connect to switch S2. The Channel 1 received signals are input to passive highpass filter FL2 through switch S3 and impedance matching resistor R3, and then output on J2. The Channel 2 received signals are input to passive bandpass filter FL1 through switch S2 and impedance matching resistor R1, and then output on J2. Switches S3 and S2 allow selection at any time between signals received from the Chirp hydrophone array and signals received from the Chirp transducers. When either switch is in the HYDROPHONE position, the Chirp hydrophone array for the respective channel is the source of the received subbottom signals. When either switch is in the T/R position, the Chirp transducers for the respective channel are the source of the received subbottom signals. Power Amplifier Board There are two Power Amplifier boards in the transceiver. On each board the Chirp transmit waveforms, the transmit gate, and the power level control signals are input on J4 from the Front Panel Distribution board. The Power Amplifier board drives the transducers with the Chirp transmit waveforms and is powered with +48 VDC, which is input on J2 from the Front Panel Distribution board. Gates U1A and U1B generate complementary drive signals that are output to the gates of transistors Q1 and Q2. These transistors drive transformer T2, which provides the gate drive signals to transistors Q6 Q13. Q6 Q13 drive output transformer T1, whose primary and secondary connect to J5. J5 connects to J6 through the voltage divider System Manual September 1999

123 CAP-6600 Chirp II Acoustic Profiling System 5-13 composed of R7 and R57 and the series resistor R72. The voltage divider allows monitoring of the voltage output at TP5 and TP6, and the series resistor allows monitoring of the output current at TP4 and TP6. The transformer s primary has a center tap that is output on J7 and connects to an energy storage capacitor bank. The output of the Power Amplifier on J6 connects to the transducers. The transmit power level control signals are input on J4 from the Front Panel Distribution board. These signals set the voltage that is output to U10, whose output controls the output of Q3. Received subbottom signals are input on J6 and applied to the differential amplifier U5 through the T/R network composed of high voltage coupling capacitors C22 and C23, and T/R diodes CR1 CR4. The T/R diodes limit the input to the differential amplifier to 1.4 V peak to peak to protect the amplifier during the transmit burst. The output of the differential amplifier drives isolation transformer T1 which outputs the received signals on J8. The Power Amplifier board includes several forms of protection: current limiting, thermal overload, low frequency input, and input isolation. The current to the transformer primary is limited through sensing resistor R71 and transistor Q5, whose output is input to amplifier U10. The output of U10 controls the output of pass transistor Q3, switching it off if the current exceeds a preset maximum. Thermal overload protection of Q3 is provided with S1, which will disconnect the +48 VDC from the Power Amplifier board if the temperature of Q3 reaches 100 C. Protection against low frequency inputs is provided by U6B, whose output disallows the transmit gate to activate the Power Amplifier output unless a minimum transmit frequency is input. The Chirp transmit waveform and transmit gate inputs are optically isolated with U2 and U3, and the transmit power level control inputs are optically isolated with U11 U13. Transformer Jumper Board There are two Transformer Jumper boards in the transceiver. Each board interfaces a multi-tapped output transformer T1 with a corresponding Power Amplifier board. The primary voltage is input at TP1 TP6. Seven secondary taps are available for selection with jumpers JMP1 JMP7. With the low and high jumper positions selected, the secondary voltage is output at TP7 and TP8. The table on the Transformer Jumper board assembly contains the standard and maximum jumper settings. SECTION 5 Theory of Operation Circuit Board Description

124 5-14 DATASONICS System Manual September 1999

125 CAP-6600 Chirp II Acoustic Profiling System 6-1 SECTION 6 Maintenance and Troubleshooting SECTION 6 Maintenance and Troubleshooting

126 6-2 DATASONICS System Manual September 1999

127 CAP-6600 Chirp II Acoustic Profiling System 6-3 T he routine maintenance of the CAP-6600 Chirp II Acoustic Profiling System involves periodic inspection of the DSP-661 Processor and the DSP-662 Transceiver air filters, backing up and maintaining the processor s internal hard drive, and washing and inspecting the tow vehicle. This section encompasses the maintenance procedures that will help ensure continued, reliable performance from the system, and troubleshooting guides that will assist in isolating and correcting any problems encountered during setup and deployment. Also, a list of recommended test equipment is provided which can be used for troubleshooting any hardware problems. Workstation Periodic Maintenance The CAP-6600 Chirp II Workstation is built from highly reliable components and requires a minimum of maintenance; however, to maintain the best performance and to avoid premature hardware failures, periodic maintenance should be performed. This includes the cleaning of the air filters, making backups, and using hard disk maintenance utilities. NOTE Keeping the air filters clean is important. Dirty air filters will restrict the flow of cooling air to the hardware components which can cause heat damage and/or failure. Air Filter Removal and Cleaning The processor and the transceiver each have one filter on the front panel and two filters on the rear panel. To access the filters on the front panels, first remove the retention screws that hold the plates, and then remove the plates and the filters. To access the filters on the rear panels, first remove the snap-in retention plates, and then remove the filters. Clean or replace the filters as required. Backups It is recommended that the processor s internal hard drive be backed up on a regular basis. This will ensure, should the hard drive fail, that it can be restored to its original configuration, hence eliminating time-consuming reloading of programs and loss of data. Backups should be done on high-density, removable hard disks such as magneto-optical disks or other high-density storage media. SECTION 6 Maintenance and Troubleshooting Workstation Periodic Maintenance

128 6-4 DATASONICS Hard Disk Maintenance Utilities The regular use of hard disk maintenance utilities such as Microsoft ScanDisk and Disk Defragmenter will greatly reduce the risk of hard drive failure, data loss and degraded performance of the hard drive. NOTE Use of an external degaussing device can permanently damage the monitor. Use only the monitor s own internal degaussing device. Tow Vehicle Periodic Maintenance Maintenance of the TTV-170, TTV-190, and TTV-173 tow vehicles is required after each use including washing and inspection of cables and connectors. Cleaning and Inspection After the tow vehicle is retrieved from service, perform the steps listed below to clean and inspect the tow vehicle. 1. Wash down the tow vehicle, inside and out, with clean, fresh water and remove any debris that may have become trapped. 2. Inspect the face of the transducers and hydrophone arrays. Spray them with fresh water, and then clean them with a mild, non-abrasive detergent, being careful to remove any buildup. After cleaning, spray them again with fresh water. NOTE Do not use an ammonia-based cleaner such as a glass cleaner to clean the transducers and hydrophone arrays. 3. Check for loose cable connections or other signs of damage. The underwater connectors in the tow vehicle and on the deck cable should be kept clean. Clean the connector pins and sockets with an alcohol wipe. Also, before reconnecting any of the cables, lubricate the pins with an O-ring quality silicone or barium based lubricant. NOTE Be careful not to get any lubricant on the faces of the transducers or the hydrophone arrays as doing so will severely degrade their performance. System Manual September 1999

129 CAP-6600 Chirp II Acoustic Profiling System 6-5 System Troubleshooting If during the processor or transceiver activation, the predeployment checks, or the operation of the system, either the CAP-6600 Chirp II Workstation or the tow vehicle does not appear to be functioning properly, refer to the troubleshooting guides in this section and to the functional and circuit board descriptions in SECTION 5, "Theory of Operation." The troubleshooting guides will assist in quickly isolating the problem, and the theory of operation will assist in tracing the source of the problem to the assembly or component level. WARNING Before disconnecting any cables or removing any boards from the processor or the transceiver, be sure the VAC or VAC, Hz power source is disconnected. Field Test Equipment Below is a list of the minimum required and optional field test equipment for troubleshooting any performance problems or hardware failures. The minimum required field test equipment includes the following: Fluke 70 Series multimeter or equivalent Tektronics Model TDS-220 or TDS-210 digital oscilloscope TIF IT V megometer or equivalent ISA BUSS extender card The optional field test equipment includes the following: Wavetek Model MHz DDS function generator or equivalent Tektronics TEK 1503C metallic time domain reflectometer Leader LDC-822 digital counter or equivalent SECTION 6 Maintenance and Troubleshooting System Troubleshooting

130 6-6 DATASONICS Workstation Disassembly and Reassembly To access the hardware inside either the processor or the transceiver, first remove the four screws that secure the front panel to the rack and slide the processor or the transceiver out of the rack until the slides lock. Be careful not to snag or chafe any of the cables. Then loosen the screws that secure the cover and remove the cover. Reverse the procedure to reassemble. WARNING Be sure the workstation is well secured before sliding out either the processor or the transceiver as the workstation could tip forward. Troubleshooting Guides Troubleshooting guides for assisting in the isolation of problems that may occur prior to the tow vehicle deployment are presented in Table 6-1, Table 6-2, and Table 6-3. The tables are sequenced in the order of the processor activation procedures, the transceiver activation procedures, and the predeployment checks procedures, as presented in SECTION 3, "Setup and Deployment." All the tables present possible symptoms based on extensive field experience with the CAP-6600 Chirp II Acoustic Profiling System and recommend the corrective action for one of more possible causes of each symptom. WARNING Before disconnecting any cables or removing any boards from the processor or the transceiver, be sure the VAC or VAC, Hz power source is disconnected. When using the troubleshooting guides, perform the corrective actions for any given symptom in the order presented until the problem is corrected or isolated. When the corrective action calls for checking a board or making an adjustment, refer to SECTION 5, "Theory of Operation," for the board locations, general descriptions, and schematic and assembly drawing numbers, and to SECTION 7, "Drawings," for the schematic and assembly drawings. When the corrective action calls for checking the wiring or connectors, refer to SECTION 7, "Drawings," for the wiring diagrams. The troubleshooting guides also call for three procedures included in this section: checking the transducer cables and connectors, checking the transducers and hydrophones, and changing the jumper settings on the Transformer Jumper boards. System Manual September 1999

131 CAP-6600 Chirp II Acoustic Profiling System 6-7 Table 6-1 Processor Activation Problems Symptom Possible Cause Corrective Action The Main window does not display when choosing the Chirp2 icon. The error message "No software keylock is present" is displayed. With the default display setup consisting of the Profile - CH1+CH2 window open, the CH 1 or the CH 2 profile display does not update. The printer was turned off when choosing the Chirp2 icon. The cable from the CPU parallel port is not properly connected to the keylock or is faulty. The cables between the Burst/Receiver board and the DSP boards are not properly connected or are faulty. The Burst/Receiver board in the processor is not functioning properly. The Channel 1 DSP board is not functioning properly. Turn on or disconnect the printer, and then choose the Chirp2 icon. Check the cable that connects the CPU to the keylock. The cable is located inside the processor. Check the cables between the Burst/Receiver board and the DSP boards. Verify that a 5 V, 100 µsec key pulse is present on J6, pin 2 of the Burst/Receiver board. If not, replace the board. Refer to the DSP Board Configuration Drawing A and configure the Channel 2 DSP board for Channel 1. If the CH 1 profile display updates, replace the Channel 1 DSP board. SECTION 6 Maintenance and Troubleshooting System Troubleshooting

132 6-8 DATASONICS Table 6-2 Transceiver Activation Problems Symptom Possible Cause Corrective Action The POWER indicator does not light when the transceiver POWER switch is turned on. The tow vehicle does not begin transmitting after clicking SET in the Chirp 2 Controls window. The AC power cables are not properly connected. The +/-12 VDC power supply in the transceiver has failed. The POWER indicator LED is not functioning. The transmitter attenuations are set to OFF. The tow vehicle is not properly connected to the transceiver or the deck cable is faulty. The Burst/Receiver board is not properly connected to the transceiver. The Burst/Receiver board is not functioning properly. The +48 VDC power supply in the transceiver has failed. Check all the AC power cable connections. Check the +/-12 VDC power supply. Replace the supply if it has failed. Check the transceiver front panel LEDs and the front panel connections to the Front Panel Distribution board. In the Power Controls area of the Chirp 2 Controls window, use the Ch1 and Ch2 scroll bars to set the Channel 1 and Channel 2 transmitter attenuations to 0 db. Verify that the deck cable is properly connected to the tow vehicle and the transceiver. Refer to "Cable Checks" on page 6-14 and check the cabling and connectors in the tow vehicle. Check all the internal and external connections between the Burst/Receiver board in the processor and the Front Panel Distribution board in the transceiver. Check the Burst/Receiver board. Replace the board if it has failed. Check the +48 VDC power supply. Replace the power supply if it has failed. System Manual September 1999

133 CAP-6600 Chirp II Acoustic Profiling System 6-9 Table 6-3 Predeployment Checks Problems Symptom Possible Cause Corrective Action When running the Chirp pattern test, there is no Chirp pattern test display in the CH 1 or CH 2 profile display in the Profile - CH1+CH2 window after several minutes. When running the Chirp pattern test, the CH 1 and CH 2 profile displays in the Profile - CH1+CH2 window show wide, uncorrelated pulses, unlike that shown in Figure 3-15 on page When running the Chirp pattern test, the Chirp pattern test display appears in only one of the profile displays in the Profile - CH1+CH2 window. The Burst/Receiver board is not functioning properly. The SET button in the Chirp 2 Controls window has not been clicked. The transmit waveform file or the receive waveform file or both are missing or corrupted. The display threshold is not set correctly. Check the Burst/Receiver board. Replace the board if it has failed. Click SET in the Chirp 2 Controls window. Run the Chirp pattern test for all the Chirp pulse widths 5, 10, 20, 30, 40, and 50 msec. To run the Chirp pattern test, select Tools from the menu bar, select Diagnose, and then choose System Diagnose. To adjust the Chirp pulse width, use the Ch1 and Ch2 scroll bars in the Power Controls area of the Chirp 2 Controls window. If some or all the pulse width settings result in wide, uncorrelated pulses, perform the System Restore procedure described in "Performing the System Restore" on page A-3 or the System Setup procedure described in "Performing the System Setup" on page A-4 to restore the waveform files to the factory default status. Adjust the corresponding CH 1 or CH 2 scroll bar in the Display Threshold area of the Display Gain Setup dialog box. To open the Display Gain Setup dialog box, select Display from the menu bar, and then choose Display Gain. SECTION 6 Maintenance and Troubleshooting System Troubleshooting

134 6-10 DATASONICS Table 6-3 Predeployment Checks Problems (Continued) Symptom Possible Cause Corrective Action When running the Chirp pattern test, the Chirp pattern test display appears in only one of the profile displays in the Profile - CH1+CH2 window. (Cont.) Transmitted pulses can not be heard or felt on one or both of the Channel 1 and Channel 2 transducers. The Burst/Receiver board or the DSP board is not functioning. The burst control section of the Burst/Receiver board is not functioning. One or both of the Power Amplifier boards are not functioning. Any one or a combination of the deck cable, the multi-conductor armored tow cable if used, the block mold, or the transducer connectors are faulty. Check for the Chirp pattern signal at J6, pin 4 (+) and J6, pin 11 (-) for Channel 1, and J7, pin 4 (+) and J7, pin 11 (-) for Channel 2. If the Channel 1 or Channel 2 Chirp pattern signal is not present, replace the Burst/Receiver board. If both signals are present, check the cables to the DSP boards. If the cables are good, replace the DSP board. Select Tools from the menu bar, select Diagnose, and then choose System Diagnose to run the Chirp pattern test. The displays should look similar to those shown in Figure 3-15 on page If not, check the burst control section of the Burst/Receiver board or replace the board. Check the Power Amplifier board. Replace the board if it has failed. NOTE: If one channel is functioning, swap the Power Amplifier boards. If the transmitted pulses now can be heard or felt, replace the failed Power Amplifier board. Refer to "Cable Checks" on page 6-14 and check the deck cable, the multi-conductor armored tow cable if used, the block mold, and the transducer connectors in the tow vehicle. System Manual September 1999

135 CAP-6600 Chirp II Acoustic Profiling System 6-11 Table 6-3 Predeployment Checks Problems (Continued) Symptom Possible Cause Corrective Action Transmitted pulses can not be heard or felt on one or both of the Channel 1 and Channel 2 transducers. (Cont.) Transmitted pulses can be heard but are weak or stop periodically on one or both of the Channel 1 and Channel 2 transducers. During the tap test there is no display in one or both of the profile displays in the Profile - CH1+CH2 window. One or both of the tow vehicle transducers are faulty. The transmit duty cycle is being exceeded causing the thermal overload protection circuit on one or both of the Power Amplifier boards to activate. Any one or a combination of the deck cable, the multi-conductor armored tow cable if used, the block mold, or the transducer connectors are faulty. One or both of the tow vehicle transducers are faulty. The jumper configuration on the Transformer Jumper board is not the correct configuration for the connected tow vehicle. One or both of the hardware gain settings are set too low. One or both of the TVG settings are set too low. Refer to "Transducer Checks" on page 6-14 and check the transducers in the tow vehicle. Verify that the maximum allowable transmit duty cycle of 15% is not being exceeded. For information on how to calculate the transmit duty cycle, refer to "Chirp Pulse Length" on page 4-5. Refer to "Cable Checks" on page 6-14 and check the deck cable, the multi-conductor armored tow cable if used, the block mold, and the transducer connectors in the tow vehicle. Refer to "Transducer Checks" on page 6-14 and check the transducers in the tow vehicle. Refer to "Changing the Transformer Jumpers" on page 6-16 and reconfigure or verify the correct jumper configuration for the connected tow vehicle. In the Hardware Gain area of the Chirp 2 Controls window, use the Ch1 and Ch2 scroll bars to set the Channel 1 and Channel 2 receiver gains to 0 db or higher. Repeat the tap test. Use the TVG Ch 1 and Ch 2 scroll bars in the Chirp 2 Controls window to set the Channel 1 and Channel 2 TVGs to 1.50 or higher. Repeat the tap test. SECTION 6 Maintenance and Troubleshooting System Troubleshooting

136 6-12 DATASONICS Table 6-3 Predeployment Checks Problems (Continued) Symptom Possible Cause Corrective Action During the tap test there is no display in one or both of the profile displays in the Profile - CH1+CH2 window. (Cont.) Navigation data are not present in the Navigation-Status section of the Chirp 2 Controls window. The Burst/Receiver board or the DSP board is not functioning. Any one or a combination of the deck cable, the multi-conductor armored tow cable if used, the block mold, or the hydrophone connectors are faulty. One or both of the hydrophone arrays in the tow vehicle are faulty. The cable from the navigation system is not properly connected to the processor. Select Tools from the menu bar, select Diagnose, and then choose System Diagnose to run the Chirp pattern test. Check for the Chirp pattern signal at J6, pin 4 (+) and J6, pin 11 (-) for Channel 1, and J7, pin 4 (+) and J7, pin 11 (-) for Channel 2. If the Channel 1 or Channel 2 Chirp pattern signal is not present, replace the Burst/Receiver board. If both signals are present, check the cables to the DSP boards. If the cables are good replace the DSP board. Refer to "Cable Checks" on page 6-14 and check the deck cable, the multi-conductor armored tow cable if used, the block mold, and the hydrophone connectors in the tow vehicle. Refer to "Transducer Checks" on page 6-14 and check the hydrophone arrays in the tow vehicle. Check the COM1 serial port connection, which is the NAV connector on the back panel of the processor. Check the connection to the navigation system. System Manual September 1999

137 CAP-6600 Chirp II Acoustic Profiling System 6-13 Table 6-3 Predeployment Checks Problems (Continued) Symptom Possible Cause Corrective Action Navigation data are not present in the Navigation-Status section of the Chirp 2 Controls window. (Cont.) The settings in the Communication Port Setup dialog box are not correct. The navigation template in the Communication Port Setup dialog box is not correct. The proper RS-232 signal levels are not present. Select File from the menu bar, select Comm Ports, and then choose Comm Port Setup. In the Setup area of the Communication Port Setup dialog box, select COM1; in the Baud Rate area select 9600; in the Data Bits area select 8; in the Stop Bits area select 1; in the Parity area select NONE; in the Nav Port area select COM1; and in the Aux Port area select COM1. Select the Nav ON check box. NOTE: Depending on the navigation system the communication port setup may require different settings than those above. If a custom string is used for the navigation template, refer to the DSP-661 Processor Software Manual for more information. Check the cable from the navigation system and its connectors for the proper RS-232 signal levels. SECTION 6 Maintenance and Troubleshooting System Troubleshooting

138 6-14 DATASONICS Cable Checks If it is suspected that a cable or connector is not functioning, there are three simple checks that can be performed: inspection for signs of arcing, checking continuity, and checking for a short circuit. Arcing Check the cable and mold connectors for signs of arcing. A black carbon material or voids in the rubber are signs of arcing. If a connector has arced, both the connector and its mating connector should be cleaned thoroughly to remove all carbon and dirt. If the rubber has significantly eroded, replace the connector. Inspect the mating connector and replace it also if it shows the same symptoms. Continuity Using an ohmmeter that can read 10 ohms or less, check each wire in the cable for continuity. Refer to SECTION 7, "Drawings," for the wiring diagrams. A reading of 1 ohm or less should be observed on short cables and connector molds. The reading for deck cables will be higher. Short Circuit Test Disconnect both ends of the cable and clean the connectors. Using a megometer or a digital multimeter on the highest ohm scale, measure the resistance of each pin of the cable or connector mold to every other pin. All measurements should read greater than 10 megohms; however, a value as low as 1 megohm will allow the system to work temporarily as the short circuit is still developing. Transducer Checks If it is suspected that a transducer or a hydrophone is not functioning, there are four simple checks that can be performed: inspection for signs of arcing, tapping the face of the transducer or hydrophone and checking for a signal output, checking for a short circuit, and applying a signal to the input of the transducer and listening for a transmitted pulse. System Manual September 1999

139 CAP-6600 Chirp II Acoustic Profiling System 6-15 Arcing For a transducer, check the connector on the connector pigtail of the transducer for signs of arcing. A black carbon material or voids in the rubber are signs of arcing. If a connector has arced, both the connector and its mating connector should be cleaned thoroughly to remove all carbon and dirt. If the rubber has significantly eroded, replace the connector. Inspect the mating connector and replace it also if it shows the same symptoms. Tap Test Connect an oscilloscope to the pins of the transducer s connector. Refer to SECTION 7, "Drawings," for the wiring diagrams. Tap the face of the transducer with a screw driver handle or other smooth, light object and note the waveform on the oscilloscope. The peak voltage level should be in the hundreds of millivolts. Note that for a transducer or hydrophone array, the other transducers or hydrophones in the array should display a similar waveform and voltage for a similar tap; furthermore, if a digital oscilloscope is used, it should be possible to observe that the phases are the same. The hydrophone arrays each contain a built in preamplifier. To perform the tap test, first supply a DC voltage across the power input and power ground pins. Refer to SECTION 7, "Drawings," for the wiring diagrams. A 9 volt radio battery is ideal for this purpose. Short Circuit Test Only the AT-14F7C high frequency transducers can be tested for a short circuit. The AT-471 low frequency transducers each have an internal transformer, which appears as a short circuit when tested. Disconnect the cable from the AT-14F7C high frequency transducer. Using a megometer or a digital multimeter on the highest ohm scale, measure the resistance of each pin of the cable or connector mold to every other pin. All measurements should read greater than 10 megohms; however, a value as low as 1 megohm will allow the system to work temporarily as the short circuit is still developing. WARNING Do not use a megometer to check the hydrophone arrays for a short circuit. The hydrophone arrays each contain a built in preamplifier which could be damaged by the high voltage output of the megometer. SECTION 6 Maintenance and Troubleshooting System Troubleshooting

140 6-16 DATASONICS Before reconnecting any of the cables, clean the connector pins and sockets with an alcohol wipe, and then lubricate the pins with an O-ring quality silicone or barium based lubricant. Transmit Test Transmit into the transducer at full power. It should be possible to hear the transmit burst as a sharp, crisp pulse. Listen for voltage arcing or hissing which indicates a faulty transducer. It should also be possible to feel the transmit pulse with the hand. Changing the Transformer Jumpers Each of the tow vehicles and the AT-471 transducer array used with the CAP-6600 Chirp II Acoustic Profiling System require a specific jumper configuration on the two Transformer Jumper boards. Hence when a different tow vehicle is connected to the DSP-662 Transceiver, the jumper configuration on the Transformer Jumper board may require changing. Before connecting a different tow vehicle, refer to SECTION 7, "Drawings," for the assembly drawing of the Transformer Jumper board, which is Drawing B In addition, refer to Figure 6-1 for the location of the Transformer Jumper boards, and then perform the steps listed below to reconfigure or verify the jumper configurations on both boards. 1. Turn off the DSP-662 Transceiver. WARNING Be sure the workstation is well secured before sliding out the transceiver as the workstation could tip forward. 2. Remove the four screws that secure the transceiver front panel to the rack and slide the transceiver out of the rack until the slides lock. Be careful not to snag or chafe any of the cables. 3. Loosen the screws that secure the transceiver cover and remove the cover. 4. Locate the two Transformer Jumper boards, one connecting to the Channel 1 Power Amplifier board, and the other to the Channel 2 Power Amplifier board. 5. Refer to the leftmost column in the table in Drawing B and locate the model number of the tow vehicle that is to be connected. System Manual September 1999

141 CAP-6600 Chirp II Acoustic Profiling System 6-17 JUMPERS (2) TRANSFORMER JUMPER BOARD (CHANNEL 2) JUMPERS (2) TRANSFORMER JUMPER BOARD (CHANNEL 1) Figure 6-1 Location of the Transformer Jumper Boards 6. In the STANDARD column under LOW FREQUENCY CHANNEL 1, determine the HIGH and LOW jumper settings for the tow vehicle. 7. Locate the jumper sockets (JMP1 JMP6) on the Transformer Jumper board that connects to the Channel 1 Power Amplifier board. Two of the jumper sockets should have a jumper already installed. 8. Reconfigure the jumper settings by removing and reinstalling as necessary the two jumpers in accordance with the HIGH and LOW jumper settings determined in Step In the STANDARD column under HIGH FREQUENCY CHANNEL 2, determine the HIGH and LOW jumper settings for the tow vehicle. 10. Locate the jumper sockets (JMP1 JMP6) on the Transformer Jumper board that connects to the Channel 2 Power Amplifier board. Two of the jumper sockets should have a jumper already installed. SECTION 6 Maintenance and Troubleshooting System Troubleshooting