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pulseEKKO PRO

3-System Setup Parameters

49

3.3.5.2

Set Odometer Manually

When Odometer Calibration is selected, the user is prompted to manually enter the odometer calibration
factor. In general, this method of odometer calibration is not recommended because it will not be as
accurate as calibrating the odometer over a known distance.

3.3.5.3

Odometer Direction

This setting determines whether data are collected as the system is rolled forward or reverse. The back up
arrow (Section 6.6.2: P89) will work in the direction opposite to this setting. The available options are:
Forward and Reverse.

3.3.6 Fibre Optic Testing

As part of troubleshooting a problem with the system, the fibre optic cables can be tested for damage
(Section 7.2: P99). 

Summary of Contents for pulseEKKO Pro

Page 1: ...USER S GUIDE Copyright 2005 Sensors Software Inc 2005 00040 01 pulseEKKO PRO ...

Page 2: ...TWARE PRODUCT for backup purposes in support of your use of the product on a single workstation You may not copy distribute or sell copies of the SOFTWARE PRODUCT or accompanying written materials including modified or merged SOFTWARE PRODUCT to others sell licence sublicence assign or otherwise transfer this licence to anyone without the prior written consent of SSI modify adapt translate decompi...

Page 3: ...abuse or misapplication SSI shall have no responsibility to replace the SOFTWARE PRODUCT refund the licence fee or replace or repair the HARDWARE PRODUCT Do not tamper with any PRODUCT PRODUCT contains no user serviceable parts If tampering is evident in SSI s opinion warranty is void and null No oral or written information or advice given by SSI its dealers distributors agents or employees shall ...

Page 4: ...agreements oral or written between the parties relating to the subject matter of this agreement Should you have any questions concerning this agreement please contact in writing Sensors Software Inc 1040 Stacey Court Mississauga Ontario Canada L4W 2X8 Tel 905 624 8909 Fax 905 624 9365 E mail radar sensoft ca pulseEKKO Noggin SpiView SnowScan Conquest SmartCart SmartHandle Conquest for Windows Win_...

Page 5: ...ing the Transmitter and Receiver to the Mounting Blocks 9 2 3 6 Inserting Batteries into the Transmitter and Receiver 10 2 3 7 Attaching Handles 11 2 3 7 1 Attaching the Adjustable Handles 11 2 3 8 Connecting the Fibre Optic Cables 12 2 4 High Frequency Transducer Assembly 14 2 4 1 High Frequency Transducers 14 2 4 2 Mounting Transducers to the Skid Plate 15 2 4 3 High Frequency Hand Towed System ...

Page 6: ...val 36 3 2 3 1 Determining the Number of Points per Trace 36 3 2 4 Antenna Separation 37 3 2 5 Antenna Step Size 38 3 2 6 Radar Velocity 39 3 2 7 System Stacking 40 3 2 8 Pulser Setting 41 3 3 Acquisition Control 42 3 3 1 Trigger Method 42 3 3 1 1 Triggers 43 3 3 1 2 Odometer 43 3 3 1 3 Free Run 43 3 3 2 Beeper Activated 43 3 3 3 Free Run Trace Delay 44 3 3 4 GPS Parameter Menu 44 3 3 4 1 GPS Reco...

Page 7: ... 3 5 1 Trace Plotting Type 56 3 5 2 Gain Type Applied and Gain Applied 58 3 5 2 1 AGC Gain 58 3 5 2 2 SEC Gain 60 3 5 2 3 Constant Gain 61 3 6 DVL Setup Menu 63 3 6 1 Set DVL Time and Date 63 3 6 2 Set DVL Transfer Mode 63 3 6 3 Set DVL into Upgrade Mode 63 3 6 4 Select Display Info Mode 64 3 7 View Complete Setup 64 3 8 Return 64 4 Running in Scope Mode 65 4 1 Scope Screen 66 4 1 1 Adjusting Time...

Page 8: ...1 Low Frequency Reflection Profiling Mode 82 6 1 1 Two Person Operation 82 6 1 2 One Person Operation 83 6 1 3 Strain Relief for Fibre Optic Cables 84 6 1 4 Maintaining Proper Antenna Separation 84 6 1 5 Antenna Movement 85 6 2 High Frequency Reflection Profiling Mode 85 6 2 1 Tow Mode Operation 85 6 3 Antenna Orientation 86 6 4 Triggers 87 6 5 Free Run 87 6 6 Odometer Data Acquisition 88 6 6 1 Sk...

Page 9: ...lem No Signal on Screen 101 7 6 System Overheating 102 7 7 DVL Problem 102 7 8 Timezero Jitter 102 7 9 System Runs But Data Does Not Look Right 103 7 10 Contacting Sensors Software Inc 103 8 File Management 104 8 1 Connecting the DVL to a PC 105 8 2 Installing and Running the WinPXFER Software on a PC 106 8 3 Transfer Directory 106 8 4 Transfer File 107 8 5 Delete Directory 108 8 6 Delete File 109...

Page 10: ...s 117 10 4 Spares 117 Appendix A Data File Formats A 1 Appendix B GPR Signal Processing Artifacts B 1 Appendix C Excerpts from the HP Fiber Optic Handbook C 1 Appendix D Health Safety Certification D 1 Appendix E FCC Regulations E 1 Appendix F Instrument Interference F 1 Appendix G Safety Around Explosive Devices G 1 ...

Page 11: ...ck Start to Data Collection on page 32 Scope Mode Section 4 Running in Scope Mode on page 65 describes how to set timezero to ensure the system is ready for data collection Data Collection Section 5 Data Collection Mode on page 69 describes running the radar sys tem and collecting data Surveying Techniques Section 6 Surveying Techniques on page 82 describes system configurations and offers hints f...

Page 12: ...ure 2 2 configurations 2 1 1 Low Frequency Hand Held There are four essential components to the low frequency radar system the Digital Video Logger DVL the control module the transmitter assembly and the receiver assembly The control module is attached to the back of the DVL The transmitter and receiver assemblies are connected to the control module via appropriate fibre optics cables Figure 2 1 C...

Page 13: ...cy radar system the Digital Video Logger DVL the control module the transmitting transducer and the receiving transducer The control module is attached to the back of the DVL The transducers are connected to the control module via the transducer cables Figure 2 2 Figure 2 2 The complete high frequency pulseEKKO PRO tow mode assembly ...

Page 14: ...ck of the DVL Figure 2 3 This may already have been done at the factory Proceed to the next section if this is the case Figure 2 3 The DVL with the control module attached to the back Figure 2 4 Remove the 4 yellow caps and the 4 screws from the back of the DVL left and place the control module on the back of the DVL right Make sure that the 37 pin connector is aligned properly with the 37 socket ...

Page 15: ...5 to 200 MHz require fibre optic cables to connect the transmitter and receiver to the control module Higher frequency shielded antennas use electrical cables to connect the transmitter and receiver to the control module The control module is designed to accept both types of cables For low frequency antennas the Electronic to Fibre Optic Converters must be attached to the control module and secure...

Page 16: ...Hz Figure 2 7 The best frequency of antenna to use on a survey depends on the survey objectives Section 3 2 1 P34 Figure 2 7 Low frequency unshielded bistatic antennas available for the pulseEKKO PRO The antennas come in pairs one transmitting antenna and one receiving antenna The shortest antennas the 200 MHz are 0 5 metres long while the longest the 12 5 MHz are 8 metres long The procedure for a...

Page 17: ...the sockets finger tight DO NOT APPLY UNDUE FORCE Figure 2 8 Hand tighten the brass sockets into the bottom of the transmitter and receiver 2 3 3 Inserting Pins into the Antennas Insert the two male brass antenna pins into the two threaded holes in the center of the antennas Tighten the pins finger tight Figure 2 9 DO NOT APPLY UNDUE FORCE Figure 2 9 Insert the male brass antenna pins into the hol...

Page 18: ...d and tightening a quarter of a turn DO NOT APPLY UNDUE FORCE It is usually best to have all four of the quarter turn fasteners properly aligned in their sockets before tightening them To do this put slight pressure on the quarter turn fastener and rotate it until you feel it drop into the socket Then align the other three quarter turn fasteners in the same manner Once complete go back and tighten...

Page 19: ... place the transmitter and receiver electronic boxes down onto the mounting blocks such that both brass pins fully connect Figure 2 11 Left Then use the 2 plastic draw latch connectors to hold the electronics boxes onto the mounting block Figure 2 11 Right Figure 2 11 Attaching the Transmitter and Receiver to the antennas ...

Page 20: ...king sure the positive terminal faces inward toward the electronics Figure 2 13 The battery is keyed with a notch in one side so it only fits properly in this orientation Close and latch the battery covers Figure 2 12 Opening the battery compartment doors Figure 2 13 Insert the 12 Volt battery into the battery compartment making sure that battery polarity is correct The positive terminal faces inw...

Page 21: ...for height by loosening the 2 levers by hand moving the handle to the desired height and retightening the levers Figure 2 15 Figure 2 14 Attach the adjustable handles to the antennas by tightening the 4 quarter turn fasteners Adjust the height of the handle by loosening the levers at the base of the handles right and pulling the handles up to the correct height Figure 2 15 Once the handles have be...

Page 22: ...cts to either fibre optic receptacle on the control module see Figure 2 18 b To connect the pulseEKKO PRO in the standard configuration shown in Figure 2 1 plug the dual fibre optics cable into the transmitter making sure the colour on the strain relief jacket matches the colour of the receptacle door black to black and grey to grey Figure 2 17 Confirm that the fibre optic connection is seated pro...

Page 23: ...bre optic converter labelled 5 Note that the fibre optic connection at the control module is keyed and will only attach properly in one orientation Figure 2 18 The dual fibre optic cable from the transmitter and receiver attaches to the electrical to fibre optic converters on the control module The fibre optic cable from the transmitter connects to the control module receptacle labelled 4 while th...

Page 24: ...he label e g T500 while the receiving transducer is indicated with an R on the label e g R500 The best frequency of antenna to use on a survey depends on the survey objectives see Antenna Frequency Section 3 2 1 P34 Figure 2 19 High frequency shielded bistatic antennas available for the pulseEKKO PRO The antennas come in pairs one transmitting transducer and one receiving transducer These are indi...

Page 25: ...two side flanges top The transducers are placed onto the bottom skid plate with the labels facing the same direction middle with the receiving transducer R500 in front of the transmitting transducer T500 The transducers are held onto the skid plate by placing the two flanges over the mounting posts The above images show the assembly of the 500 MHz transducers onto the 500 MHz skid plate The proced...

Page 26: ... 4 3 1 Attaching the Adjustable Tow Handle Figure 2 21 To attach the adjustable tow handle to the skid plate assembly place the T end of the handle into the trough on the end of the skid plate assembly where the receiving transducer label is facing The T end of the handle is attached to the skid plate assembly by placing the U bracket over the top and into the vertical slots The handle is secured ...

Page 27: ...ches to the skid plate assembly exactly the same way as the adjustable tow handle is attached Place the T end of the odometer into the trough on the end of the skid plate assembly The labels on the transmitting transducer should be facing away from this end The T end of the odometer is attached to the skid plate assembly by placing the U bracket over the top and into the vertical slots The odomete...

Page 28: ...nnect to receptacle 1 on the control module Figure 2 24 The Big Wheel Odometer and odometer cable can be seen in the complete system configuration See Figure 2 2 on page 3 Figure 2 24 The Big Wheel Odometer uses a long extension cable not shown to attach to receptacle 1 on the control module To acquire data with an odometer the Trigger Method must be set to Odometer Section 3 3 1 2 P43 ...

Page 29: ...bles to the transducers The connections are secured with latches Figure 2 26 Connecting the transducer cables to the Control Module The transducer cable from the transmitting transducer connects to the control module receptacle labelled 4 while the transducer cable from the receiving transducer connects to the con trol module receptacle labelled 5 The cable attachments are secured with latches ...

Page 30: ...Beeper Activated option Section 3 3 2 P43 is set to CANBUS Another method of triggering the system is to set the Trigger Method to DVL button Section 3 3 1 1 P43 and the Beeper Activated option to CANBUS Section 3 3 2 P43 Pressing the B button the DVL will trigger the system to acquire a data trace and an audible beep from the electrical beeper trigger unit will indicate when data are being collec...

Page 31: ...s the proper connection of the Fibre Optic Remote Beeper Trigger unit Ensure that 1 The second fibre optic cable of the dual cable connects to the Output grey fibre optic connector on the remote trigger and beeper unit This connection enables the trigger part of the remote beeper trigger unit to work 2 The short single fibre optic cable connects from the Input black fibre optic connector on the re...

Page 32: ... hours of heavy use so it is a good idea to have spare 9 Volt batteries available Lithium 9V batteries are also available that will power the unit for approximately 20 hours When the voltage from the battery is gets too low the red light on the top of the Fibre Optic Remote not visible in the figures will start to flash This indicates that the battery should be replaced within approximately 30 min...

Page 33: ...ar system is run with the Trigger Method set to Fibre Optic Section 3 3 1 1 P43 data acquisition can be controlled using the thumb lever on the remote beeper trigger unit During data acquisition the beeper will emit a beep as data are being collected as long as the Beeper Activated Section 3 3 2 P43 is set to Fibre Optic 2 5 3 DVL Carrier For convenience during data acquisition the DVL and control...

Page 34: ...ometers including the wheel odometer shown in the figure which is typically used with the SmartCart Odometers attach to receptacle 1 on the control module When the radar system is run with the Trigger Method set to Odometer Section 3 3 1 2 P43 data acquisition is controlled by the odometer 2 5 5 GPS The DVL has a serial port on the back for attaching a GPS receiver This port will accommodate any G...

Page 35: ...tery Make sure that the black clip is attached to the negative and the red clip is attached to the positive battery terminals If the alligator clips are connected to the wrong terminals of the battery the DVL will not be powered When the DVL is receiving power the upper red light on the front of the DVL will be illuminated Figure 2 34 Attach the Control Module to Power Supply Cable to receptacle 3...

Page 36: ...low voltage indicator can be helpful for identifying when the battery needs to be recharged If the battery voltage drops too low the DVL will cease to operate The front of the DVL is shown in Figure 2 35 To start the system press any button on the front panel The DVL will begin to beep indicating it is booting up The lower red LED on the front panel should illuminate Figure 2 35 Digital Video Logg...

Page 37: ...Turn the DVL on by pressing any button on the front After the DVL boots up the main menu is displayed Figure 2 36 There is also a flow chart of the complete menu system on the DVL shown in Figure 2 37 Figure 2 36 pulseEKKO PRO main menu screen on the DVL To begin acquiring data press button number 1 for Run pulseEKKO GPR Details about data collection are given in Section 4 on page 65 To setup data...

Page 38: ...the same settings as before it was last powered off Therefore the user should NOT shut off the DVL by only removing the power The two numbers displayed in the lower left corner of the main menu are the internal temperature of the DVL in Celsius and Fahrenheit and the voltage of the power supply running the DVL When the DVL voltage drops to 10 2 Volts or less the DVL will shut down If this occurs i...

Page 39: ...Mode GPS Transfer Baud Rate GPS Transfer Parity GPS Transfer Stop Bits GPS Transfer Data Bits GPS Last NMEA String Test GPS with Listing 1 GPR Parameters Sampling Interval Time Window Antenna Frequency Antenna Separation Antenna Step Size Radar Velocity System Stacking Pulser Setting 3 Survey Parameters Positional Units Antenna Step Size Start Position Data Directory No Survey Type GPR Grid Type X...

Page 40: ...for running a pulseEKKO GPR system 2 On a menu with items that are not numbered one of the menu items will be flashing to indicate that it is currently selected Pressing the button immediately below the word Up or Down to choose another option Once the menu item is flashing it can be changed to preset values by pressing the A or B buttons Pressing the button under Return will take the user up to t...

Page 41: ...pecific to the GPR system Select View Complete Setup from this menu to quickly locate the desired parameter and the heading it is listed under Selecting View Complete Setup from this menu or View Setup from the main menu See Figure 2 36 on page 27 displays all the current parameter settings for the pulseEKKO PRO system A screen display similar to the one in Figure 3 2 will be seen Figure 3 2 The V...

Page 42: ...a Collection All the system parameters are detailed in this section but for a quick start to data collection the most important parameters to consider before proceeding to the next section Running in Scope Mode and starting data collection are 1 Frequency Section 3 2 1 P34 2 Time Window Section 3 2 2 P35 3 Sampling Interval Section 3 2 3 P36 4 Antenna Separation Section 3 2 4 P37 5 Antenna Step Si...

Page 43: ...3 This section describes in detail each parameter listed in this menu Figure 3 3 The GPR System Parameters menu Use the Up and Down buttons to move to the desired parameter and edit the value by pressing the A and B buttons Several of the parameters have suggested values indicated by an asterisk but these val ues can still be changed by the user ...

Page 44: ... GPR Parameters Antenna Frequency The following table offers a guide to frequency selection It is based on the assumption that spatial resolution of the target is about 25 of the target depth The values are based on practical experience and should be used as a quick guide only Note that the hardware cannot determine which antenna is attached The user must correctly enter this parameter It is impor...

Page 45: ...not the value can be changed by the user Since the radar system really measures time and survey targets are at a specific depth an estimate of velocity can be used to relate depth to time to obtain a good time window value The DVL automatically calculates and displays a depth value based on the Time Window value and the current Radar Velocity value Section 3 2 6 P39 3 2 2 1 How Depth is Determined...

Page 46: ...g Interval value will be set to a default value based on the antenna frequency selected Section 3 2 1 P34 as shown in the table below It can however be changed In general the default Sampling Interval should NOT be changed by the user The recommended temporal sampling interval versus antenna frequency is reproduced below It is important not to choose a sampling interval that is too large for a par...

Page 47: ...ncy selected Section 3 2 1 P34 as shown in the table below The rule of thumb is that the minimum antenna separation should equal the antenna length For example 100 MHz antennas are 1 metre long and should be kept about 1 metre apart during a survey If the antenna spacing is too small receiver electronics may be overloaded by the transmit signal resulting in data clipping see Appendix B GPR Signal ...

Page 48: ...e will be set to a default value based on the antenna frequency selected Section 3 2 1 P34 as shown in the table below Note that the default values can be overridden by changing the Step Size value directly When using an odometer to collect data make sure that odometer has been properly calibrated Section 3 3 5 1 P48 otherwise positional information will be incorrect In CMP mode Section 6 11 P91 t...

Page 49: ...ity value does NOT affect the quality of the GPR data collected It will only affect the depth scale on the display This can be changed later If it is not possible to determine the radar velocity directly refer to the chart below which lists the radar velocities of various materials A velocity of 0 1 m s or 0 33 ft ns is a good value to use when uncertain about the velocity of the material being su...

Page 50: ...s data quality it may slow down survey production The more stacks the longer it takes to collect data at each survey position Therefore it is important to find the optimum number of stacks that still reveal the target adequately This parameter is set under System Setup GPR Parameters System Stacking While stacks can be set from 1 to 32767 for most surveys stacking 4 to 64 times is suitable Stackin...

Page 51: ...the pulser voltage to a value lower than 1000 Volts As mentioned above using the PRO Auto setting for this transmitter will result in the voltage being set to the highest value in this case 1000 volts To set the transmitter to a different value say 500 volts it is necessary to edit the Pulser Setting until PRO 500V is displayed Note that if you have a 400 volt or 1000 volt transmitter and you try ...

Page 52: ...sing the A and B buttons Selecting any of the last three options opens sub menus to edit these parameters 3 3 1 Trigger Method The Trigger Method determines what device is going to trigger the transmitter to fire and collect a data trace This parameter is set under System Setup Acquisition Control Trigger Method There are 5 ways to trigger the transmitter to fire 1 DVL B Button 2 Electrical Trigge...

Page 53: ...ystem is not triggered by a particular device but runs continuously in time The system automatically collects data at regular user determined time intervals This is called Free Run mode and is best for surveys in flat unobstructed terrain where antennas can be moved easily For the position of each measurement point the system assumes the operator has moved the antennas one step size along the surv...

Page 54: ...ywhere on the surface of the Earth GPS receivers can be purchased from a number of manufacturers The DVL has a serial port on the back for attaching a GPS receiver Section 2 5 5 P24 This port will accommodate any GPS receiver that has a standard NMEA string output through the serial port The GPS receiver can be set up to send one or more types of data strings These strings are called NMEA 0183 str...

Page 55: ... DVL screen indicating whether GPS data is successfully being received 3 3 4 1 GPS Recording Mode There are three GPS Recording Modes available Off mode means that a GPS receiver is not connected to the DVL so no GPS information is being logged This should be the setting if you do not have a GPS receiver Reading every x traces mode means that every time the GPR collects 1 5 10 20 or 50 traces of G...

Page 56: ...09 M 5 2 0118 79 GPVTG 10 0 T 000 2 N 000 4 K D 72 GPGSA A 3 30 10 13 24 06 4 3 2 6 3 4 36 F4 GPGGA 134222 00 4338 190397 N 07938 438255 W 2 05 2 6 153 95 M 35 09 M 5 0 0118 73 GPVTG 9 8 T 000 3 N 000 5 K D 42 GPGSA A 3 30 10 13 24 06 4 3 2 6 3 4 36 If the GPS mode is set to Reading per Trace or Fiducial Tagging AND the GPR is Run Without Saving Data Section 5 8 P81 it is still possible to log GPS...

Page 57: ...T 001 4 N 002 5 K D 70 GPGSA A 3 30 26 10 13 24 06 4 2 2 1 3 6 36 GPGGA 134713 00 4338 221086 N 07938 421365 W 2 06 2 1 152 51 M 35 09 M 5 0 0118 79 GPVTG 34 0 T 001 4 N 002 5 K D 70 GPGSA A 3 30 26 10 13 24 06 4 2 2 1 3 6 36 GPGGA 134713 00 4338 221086 N 07938 421365 W 2 06 2 1 152 51 M 35 09 M 5 0 0118 79 GPVTG 34 0 T 001 4 N 002 5 K D 70 GPGSA A 3 30 26 10 13 24 06 4 2 2 1 3 6 36 GPGGA 134713 0...

Page 58: ...displays the GPS Time Latitude Longitude and Altitude as well as other values indicating the accuracy of the GPS reading The GPS position is also displayed in a square that can be Zoomed from 2 metres square to 16384 metres square 3 3 5 Odometer Setup Menu Figure 3 7 Odometer Setup Menu 3 3 5 1 Odometer Calibration The odometer should be calibrated periodically to ensure accuracy When Odometer Cal...

Page 59: ...not be as accurate as calibrating the odometer over a known distance 3 3 5 3 Odometer Direction This setting determines whether data are collected as the system is rolled forward or reverse The back up arrow Section 6 6 2 P89 will work in the direction opposite to this setting The available options are Forward and Reverse 3 3 6 Fibre Optic Testing As part of troubleshooting a problem with the syst...

Page 60: ...ach trace increments by the Antenna Step Size Section 3 2 5 P38 The Start Position value can be changed to a non zero and even a negative value if necessary It is assumed that the units for all position and distance quantities are the units specified under Positional Units Section 3 4 3 P50 For a CMP WARR measurement the start position is the initial antenna separation 3 4 2 Antenna Step Size The ...

Page 61: ... surveys 3 4 6 GPR Grid Type The grid parameter settings in the Survey Parameters menu allow the user to modify settings specific to collecting data in organized grids This includes the grid type and line spacing Data are normally collected on a grid if the user is interested in displaying the data as a 3D volume using the EKKO_3D software or as a plan map using the EKKO_Mapper software Producing ...

Page 62: ...s start at the same baseline position usually defined as zero 0 0 Figure 3 9 The line configuration for lines collected in X Lines Only mode The convention is that X lines are parallel to the X axis For seamless integration into data processing software like EKKO_Mapper note that the lines are assumed to be collected with X positions increasing as the line moves away from the Y baseline Line numbe...

Page 63: ...s start at the same baseline position usually defined as zero 0 0 Figure 3 10 The line configuration for lines collected in Y Lines Only mode The convention is that Y lines are parallel to the Y axis For seamless integration into data processing software like EKKO_Mapper note that the lines are assumed to be collected with Y positions increasing as the line moves away from the X baseline Line numb...

Page 64: ...t does make processing easier if all the lines start at the same baseline position usually defined as zero 0 0 Figure 3 11 The line configuration for lines collected in XY Lines mode The convention is that X lines are parallel to the X axis and Y lines are parallel to the Y axis For seamless integration into data processing software like EKKO_Mapper note that the lines are assumed to be collected ...

Page 65: ...Section 3 4 3 P50 If an XY grid is being collected note that the line spacing of the X lines and Y lines can be different 3 4 8 Y Line Spacing For Y Only or XY grid data acquisition the distance between the Y survey lines needs to be specified in this menu Figure 3 10 and Figure 3 11 The distance units are assumed to be the same as those specified in Positional Units Section 3 4 3 P50 If an XY gri...

Page 66: ...B buttons 3 5 1 Trace Plotting Type The data traces can be plotted in two ways Grey scale or Wiggle Grey means each data point is plotted as a grey strip based on its amplitude Figure 3 13 If traces are plotted in grey scale the trace width in pixels can also be specified The choices are 1 2 4 or 8 pixels with 2 or 1 pixels being the usual setting For example the VGA screen on the DVL with a resol...

Page 67: ...ixels results in 4 metres of data and 8 pixels results in 2 metres of data Wiggle means the traces will be plotted as a curved line with the amplitude determining the size of the curve Figure 3 14 The wiggle traces can be plotted with shading on the Left side or negative amplitude side of the trace Wiggle L the Right side or positive amplitude side of the trace Wiggle R or with no shading Wiggle N...

Page 68: ...5 Display of a data section over buried tanks No gain was applied before plotting Note that none of the gain functions are permitted to boost a data point value to greater than 32767 or less than 32767 Values where this occurs are trapped and forced to 32767 or 32767 3 5 2 1 AGC Gain The AGC Automatic Gain Control gain attempts to equalize all signals by applying a gain which is inversely proporti...

Page 69: ...e equivalent point in the AGC function Figure 3 17 Display of a data section over buried tanks An AGC gain was applied before plotting The only user variable for the AGC gain is the Max Gain Applied value This is a number between 1 and 32767 which determines the maximum gain that can be applied to any data point This maximum gain is fixed for the whole data set A typical value would be 50 2000 dep...

Page 70: ...gain is essentially an exponential function This exponential function could in fact go to infinity Therefore as with the AGC gain some gain limiting factor must be applied This gain limiting factor is identical to the one used in the AGC gain see AGC above Figure 3 18 The SEC function has one parameters that must be specified GMAX is a limiting value on the function The Atten uation alpha value de...

Page 71: ...r required is the constant factor to multiply all data points by Thus if the user enters the number 10 all data points will be multiplied by a factor of 10 This will gain strong signals and weak signals equally and result in the clipping of strong signals The advantage of a constant gain is that it is easy to understand how the amplification works The disadvantage of a constant gain is that it ten...

Page 72: ...3 System Setup Parameters pulseEKKO PRO 62 Figure 3 21 Display of a data section over buried tanks A Constant gain was applied before plotting ...

Page 73: ...3 22 DVL set time and date screen 3 6 2 Set DVL Transfer Mode When transferring data from the DVL to a PC Section 8 1 P105 two different types of PXFER cable are available Normal and Turbo For the data transfer to be successful the DVL Transfer Mode specified in this menu must be set to the correct cable Normal PXFER cables have black bands near the ends while the Turbo PXFER cables have pink band...

Page 74: ...imal number of messages are written In Display Info mode detailed messages about every system interaction are written to the screen In general it is best to use Normal mode unless you are trying to troubleshoot a system problem Section 7 P95 3 7 View Complete Setup The View Complete Setup option displays a listing of the current setup parameters for the pulseEKKO PRO See Figure 3 2 on page 31 3 8 ...

Page 75: ...sing the A and B buttons Scope mode is used to make sure that connections are correct all parameters are properly set and valid data are being collected Scope mode displays the radar trace in the traditional oscilloscope scan format see Figure 4 2 Scope mode should normally be run first prior to data collection and storage Data cannot be saved in Scope mode Once the user is satisfied that everythi...

Page 76: ...The parameters below the graph the trace number time win dow sampling interval DeltaT points stacks and frequency are listed Section 3 P31 The Offset parameter listed is explained below The Offset is the value used to adjust the first break to the ideal region The value has no importance to the radar data it is only used for the adjustment of the initial radar pulse to the desired position within ...

Page 77: ...ion of transmitter and receiver antennas and the total time window To set timezero the transmit and receive antennas should be set to the antenna separation being used for the survey Section 3 2 4 P37 This assures a large first arrival with minimal propagation delay The start of the second division represents the ideal location for timezero see Figure 4 2 The purpose is to adjust the timezero loca...

Page 78: ...hat the pulse is shifted in each step Generally 1 or 5 work well The higher values tend to shift the pulse in large steps and it is easy for the pulse to shift a long way very quickly In general timezero should be found near an Offset value listed on the scope screen of around zero ns If no transmit pulse is found then there is a problem with the transmitter Section 7 5 P101 Once the user is happy...

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