Geonics Limited EM61MK2win, EM61-MK2 Operating Instructions Manual

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OPERATING INSTRUCTIONS

EM61-MK2 DATA LOGGING SYSTEM

FOR WINDOWS 10 BASED FIELD TABLET COMPUTER

EM61MK2win

Version 1.00

May, 2018

Geonics Limited

1745 Meyerside Drive, Mississauga, Ontario, Canada L5T 1C6 Tel: (905) 670 9580 Fax: (905) 670 9204

E-mail: geonics@geonics.com

Table of Contents

1. Introduction ................................................................................................ 1

1.1 Program Requirements ......................................................................... 2

1.2 Installing EM61MK2win ....................................................................... 2

1.3 Running EM61MK2win Program ........................................................... 2

1.4 Main Screen ....................................................................................... 3

Short description of Main Screen options ...............................................................3

2. Survey Setup ............................................................................................... 5

3. System Setup ............................................................................................... 9

4. Set Port for GPS & Monitoring..................................................................... 13

4.1 GPS Port Setup .................................................................................. 13

4.1 Monitoring GPS Receiver Output ........................................................ 16

5. Display Options ........................................................................................ 19

6. Logging Data ............................................................................................ 21

6.1 Monitoring Mode .............................................................................. 21

Description of Monitoring Mode Options .............................................................24

6.2 Stand By Mode .................................................................................. 31

6.3 Logging Mode ................................................................................... 34

6.4 Stand By Mode Field Options ............................................................. 35

7. View Data Files .......................................................................................... 43

Appendix A ....................................................................................................... 47

A.1 Description of Data File in EM61MK2win Format ................................. 47

A.2 Conversion Factors ............................................................................ 50

A.3 Example of File in EM61MK2win Format ............................................. 52

Appendix B ....................................................................................................... 53

B.1 Using the EM61MK2win with a GPS Receiver ....................................... 53

B.2 Description of GGA and GSA Data Messages ...................................... 54

1. Introduction

e Geonics EM61MK2win Data Logging System (DAS70-win) consists of a tablet/laptop eld computer, data logging program EM61MK2win, and associated cable to connect the computer to the Geonics EM61-MK2 instrument. e program EM61MK2win is designed for a IBM PC compatible computer and MS Windows 10 (or 7) operating system.

e program is prepared for the MS Windows 10 tablet Mesa2 (manufactured by Juniper Systems) operated in the vertical mode display with the default setup. However the program can be used in other Windows 10( or 7) based eld computers with vertical and horizontal oriented displays. e minimum supported display resolution is 800 x 600 pixels. In case high resolution display is employed, it is advised to set fonts to 125% or 150% to increase legibility of the screen. e maximum size of program main windows is 1024 x 762 pixels.

e EM61MK2win program acquires and records survey data from the EM61-MK2 system, under the control of the operator. It also records various eld information such as survey line number (line name), starting station, increment, comments, etc. Readings are displayed in graphic and numeric mode. Readings are displayed in real time in mV. In addition, the program allows you to monitor the instrument output while data is not recorded. e EM61MK2win program continuously monitors the condition of the instrument battery, without leaving the program. e EM61MK2 also provides the possibility of automatic nulling of the instrument output at any time during the survey.

e program allows the user to set the EM61-MK2 into a specic instrument mode of operation: AUTO, Wheel, or Manual modes. In AUTO mode readings can be automatically recorded in desired time intervals. In WHEEL mode readings are triggered by a counter installed at the EM61-MK2 wheel assembly, and in MANUAL mode readings are triggered manually by the operator.

e program supports the standard EM61-MK2 instrument as well as EM61-MK2 High Power unit. It also recognizes all versions of instrument rmware automatically. e program allows you to record data while using various EM61-MK2 antenna (1 x 0.5 m, 1 x 1 m, or 0.5 x 0.5 m sensors) and Geonics EM61HH-MK2 Hand Held sensor.

e EM61MK2win will accept NMEA-0183 compatible data from a GPS receiver directly connected to an Allegro eld computer. GPS data which are embedded in the EM61MK2win data le can be processed later in the Geonics DAT61MK2 program. e connected GPS must be able to stream NMEA-0183 compatible messages. e EM61MK2win uses two NMEA messages GGA and GSA. While message GGA is mandatory, the GSA string is used only to provide information related to the GPS signal quality during data collection.

e EM61MK2win program records data together with a time stamp at each station. Data les created with this program can be used to position a survey according to locations recorded separately by a Global Positioning System (GPS).

Survey setup parameters are saved in a conguration le, therefore they can be automatically used during subsequent data collection sessions.

Data les are saved to the user selected data directory. Data le names, which can be set by the program based on the computer clock or user specied, have extension names R61. Files can be converted to M61 format and viewed in DAT61MK2 program. Number of readings in a data le is limited only by the hard drive capacity, however it is strongly recommended to avoid huge data les (i..e one to two hours long data les are adequate). e maximum speed of data collection is approximately 18 readings per second assuming 5 Hz (or less) GPS input.

EM61MK2win Data Logging System (DAS70-M2)

1.1 Program Requirements

To successfully use this software, you will need :

Computer

- Mesa2 eld computer (or similar) operating under Windows 10 or 7,

- minimum 4 Gb of RAM memory,

- USB port or other mean to transfer les,

- minimum 800 x 600 pixel display resolution,

- serial Ports: one serial port for instrument plus one serial port if directly connected GPS receiver is to be used (USB to multiple RS-232 ports adapters can be used) or available Bluetooth connection in serial port mode.

Geonics EM61-MK2

e EM61-MK2 instrument with associated cables (or Bluetooth option).

e EM61MK2win program may be stored on DAT61MK2 CD disk and it is available for download from the Geonics web site. All necessary conguration les (with extension names .INI) are created in your eld computer after the program is run for the rst time.

1.2 Installing EM61MK2win

e program consists of a standalone le EM61MK2win.exe, no DDLs nor other libraries are required to run this program.

If the program le is included separately on the DAT61MK2 CD disk, or downloaded from the web site it can be installed by copying the EM61MK2win.exe le to any directory on your hard disk. is can be performed by using Windows Explorer.

After you run the program for the rst time it will create permanent conguration le (.INI) which contain some of the program settings. If the above le does not exist on the default drive they will be created with default parameters during the rst execution of the program.

e EM61MK2win data les contain extension name R61 and their base names should be limited to 8 characters.

1.3 Running EM61MK2win Program

Start EM61MK2win by double clicking the EM61MK2win icon in the Start|Programs menu, in Windows Explorer, or on the desktop if a shortcut was created. At the start, EM61MK2win displays the following screen.

e EM61MK2win is a command button and dialog driven program. Command buttons can be executed by taping (if touch screen is used) or clicking with the left mouse button, or by pressing the indicated (underlined) character on the keyboard, or by using TAB to scroll through the buttons and ENTER to execute. In the Main Screen of the program Up and Down arrow keys can be also used to scroll through the buttons.

e Main Screen appears always as the rst window after the program is started. It contains the name of the program, its version number, and list of command buttons with available options on

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the right side. e major , left portion of the window contains information about current survey and system settings. is section is updated in real time as soon as the program parameters are changed in dialogs.

1.4 Main Screen

e Main Screen always appears after the program is started. It contains the name of the program, its version number, and a list of buttons representing the available options. e EM61MK2win Main Screen is displayed below.

ese options are selected by clicking on buttons, or from keyboard using TAB/ENTER or shortcuts indicated by underline label characters. In case of Main Screen buttons the Down and Up arrow keys and <ENTER> can be used as well.

Short description for each of the options follows.

Short description of Main Screen options

Logging

is option allows to monitor and log the EM61-MK2 output. e Logging screen starts always in Monitor mode, and then after a data le is created Logging mode is available. Monitor mode provides several options: the instrument nulling, performing Internal and External QC coil calibration, monitoring EM61-MK2 battery level, monitoring quality of GPS signal, etc.

EM61MK2win Data Logging System (DAS70-M2)

Survey Setup

e Survey Setup dialog will be displayed. All survey settings (survey line name, increments, etc.) can be specied in this dialog.

System Setup

Dialog window that is associated with this option is used to set the instrument type, antenna size, serial port numbers, battery warning level, and type of pause key.

Set GPS Port

e GPS Port Setup dialog allows to disable and enable GPS data acquisition. is option is also used to set the serial port number used for GPS input and to specify necessary serial port communication settings. GPS monitoring window can be accessed from this dialog as well.

GPS Monitoring

e program enters terminal mode and displays input from GPS. is function is very convenient to test communication with GPS receiver and examine GPS stream type.

Display Options

e dialog which will allow you to specify colour and thickness of prole lines will appear. is dialog provides also choice of linear or compressed amplitude used for prole display.

View Files

is option can be used to open collected data le and display survey line proles.

Exit

is option will terminate the program execution.

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2. Survey Setup

e Survey Setup dialog, presented below, contains several parameters which aect two important procedures: instrument settings (instrument mode, frequency of data collection, etc.) and survey geometry layout (survey line names, line spacing, start station, station increment, etc.).

To select any option click on the corresponding drop-down list box or text box, or use TAB key to scroll to the option and then use mouse or the Down and Up keys in drop-down box (parameters that have only a few possible options), or keyboard for text box entry.

Description of Options and Parameters:

EM61-MK2 Mode

is option allows you to select the type of instrument used. In the drop-down list box select Standard for the EM61-MK2 or High Power if EM61-MK2 High Power (HP) modication is used.

Set the EM61-MK2 mode of operation by selecting an item from the drop-down listbox labeled EM61 Mode. Available modes are: Auto, Wheel, and Manual. ese modes of operation are described below.

EM61MK2win Data Logging System (DAS70-M2)

Auto Mode

Readings will be triggered automatically at a specied frequency (see option Readings/s). Please note that while in the former data acquisition system (DAS70) Stn Increment (station increment) had only two options: Positive or Negative, in the current program this value is optional.

Wheel Mode

Readings will be triggered automatically by a counter attached to the wheel. Wheel increment is approximately 20 cm (or 0.64 foot) for the EM61-MK2 equipped with 1 x 0.5 m or 1 x 1 m antennas. e Hand Held EM61HH-MK2 has two wheel increments 0.1 and 0.2 m. Check the wheel increment setting on the antenna assembly.

When Wheel mode is selected option Reading/second is not available, see gure below. Please note that while in former data acquisition system (DAS70) Stn Increment (station increment) had only two options: Positive or Negative, in the current program this parameter is optional and its value has to be entered according to used wheel increment.

Manual Mode

Readings will be taken only while the manual trigger (switch on the logger cable) is pressed. is mode may be used only in very specic applications since the highly

dynamic EM61-MK2 response requires nely spaced data points. Please note that when Manual mode is selected option Reading/second is not available.

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Readings/second

When this option is available (only in Auto mode) activate text box by tapping or using TAB key and then enter desired value. is parameter describes number of readings per second that will be taken.

ere is a dierence between EM61-MK2 units whether they include the communication option or not.

In cases of older units not using Bluetooth any number larger than zero can be entered, however the EM61-MK2 maximum frequency of data output is approximately 15 readings per second. For values lower than 15 readings/s the real rate of data collection will be relatively close to specied value.

e EM61-MK2 with Bluetooth communication has a slightly dierent way of streaming data. Again any number larger than zero can be entered, however in this EM61-MK2 model the hardware xed frequency of data output is 18 readings per second. Any entered value is rounded to the nearest possible base frequency of the instrument, i.e. user specied frequency of 14 or more readings/s will result in the eective data acquisition rate of 18 readings/s (every reading is logged), 10 readings/s will cause the program to log at a rate of 9 readings/s (every second reading from instrument output is logged), etc. At slower rates the dierence between specied and eective frequencies is negligible.

Survey Line (survey line name)

Activate text box by clicking with a mouse left button or using TAB key and then enter desired name (number) for the survey line.

is is a user’s tag number/name for the prole line. e length of the name can not exceed 8 characters. e line name is usually used as a coordinate perpendicular to the survey lines direction. For example, when survey lines are laid out along W-E direction stations describe W-E coordinate, while Line names may describe S-N (vertical on a map) coordinate.

Line Incr. (survey line name)

Activate text box by clicking with a mouse or using TAB key and then enter desired for the survey line increment.

is parameter species the distance by which survey lines will be separated. is setting will be used to determine number (name) of the next survey line.

Sequence

When this option is highlighted and drop-down box is expanded use mouse or use Down or Up cursor key to toggle between two available settings: Alternate and One Way.

EM61MK2win Data Logging System (DAS70-M2)

Alternate is used when neighboring lines are surveyed in the opposite direction, which is the most common procedure during eld surveys.

One Way is used when each survey line is traversed in the same direction. e choice of this parameter will aect the default start station, a signature of the station

increment, and line direction when parameters for the next survey lines is determined.

Direction

Clicking on the down arrow next to the text box opens a drop-down box showing the available options, or when the keyboard is used activate the text box and then by using up or down arrow keys select one of four available settings: East, West, South, and North.

is parameter indicates the heading of the survey line.

Start Station (start station of a survey line)

Activate text box by clicking or using TAB key and then enter the desired value for the start station.

is parameter species the starting station number for the selected survey line. is value is used in conjunction with Station Increment to calculate the current station number for display purposes.

Stn Increment (station increment)

Activate text box by clicking with a mouse or using TAB key and then enter the desired value for the station increment.

is parameter species the station increment for the selected survey line. is value is used in conjunction with Start Station to calculate the current station number for display purposes.

After all the parameters in the Survey Setup dialog are updated click on the button OK or press ENTER key to accept the displayed settings. e program will return to the Main Screen. Updated settings will be written to the initial le and they will be given as default parameters in the subsequent Survey Setup dialog.

To return to original settings (state before this dialog was selected) click on the Cancel (X) button or press Esc key. All parameters will be reset to initial settings and the program will return to the Main Screen.

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3. System Setup

is dialog allows you to specify used type of the instrument, EM61-MK2 antenna size and set several parameters in the logging program. e System Setup dialog is presented below.

Description of Parameters:

EM61-MK2

is option allows you to select type of used instrument. In the drop-down list box select Standard for the EM61-MK2 or High Power if EM61-MK2 High Power (HP) modication is used.

Sensor Size

e Sensor Size option allows you to select the size of the EM61-MK2 sensor. If the EM61HH-MK2 Hand Held antenna is used this option can be ignored, the program recognizes Hand Held antenna connection automatically. If the standard antennas are used (1 x 0.5 m, 1 x 1 m, or 0.5 x 0.5 m) the size of the sensor must be specied before monitoring the instrument output. Select proper size of the EM61-MK2 sensor in the drop-down list box labeled Sensor Size.

EM61MK2win Data Logging System (DAS70-M2)

Battery Warning

Specify instrument battery warning level. When the EM61-MK2 battery voltage will reach and drop below specied value the program will display battery voltage on the red background.

EM61 Port

e number of serial port that is assigned to the EM61-MK2. Available selections: COM1 to COM60. e program default is COM1. Communication parameters for the selected

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serial port are set by the program, since the EM61-MK2 operates at xed settings: Baud Rate (9600), Parity (N), Data Bits (8), and Bit Stop (1).

is port must be dierent than the port specied in the list box "GPS Port:" (see below) or in the GPS Port Setup dialog window (see chapter 4), otherwise a message will be displayed and ports will have to be reassigned.

Select port number in the drop-down list box.

GPS Port

e number of serial port that is assigned to the GPS receiver. Available selections: COM1 to COM60. e program default is COM2. Communication parameters for the selected serial port can be set in GPS Port Setup dialog. e GPS port can be also assigned in the latter dialog.

is port must be dierent than the port specied as the EM61-MK2 serial port. Select port number in the drop-down list box similarly to EM61-MK2 port assignment

procedure.

Audio

Two selections are available: Yes or No. e audible click will be generated at each reading when this option is enabled. At fast rate (above 5 readings/s) the sound may appear not uniform, however this does not aect quality of data acquisition.

Display Units

ree selections are available: Meters, Feet or US Survey Feet.

Pause key

Four selections are available: any key, Enter, Space Bar, and P is feature is used to pause data recording during logging session. Default setting any key can be changed to one of the three specic keys for eld conditions where a logger key can be accidentally pushed causing unwanted stop of data logging. When Windows based tablet computer Mesa2 is used the best setting is <ENTER> key, since user specied keys P1, P2, and P3 may have various assignment, and when <any key> is selected then only four arrow keys and Enter key are reliable.

EM61MK2win Data Logging System (DAS70-M2)

Disable Pause Button (for Touch Screen)

is option is useful when Mesa2 and similar computer with enable touch screen are used. It helps avoiding logging procedure by accidental touch of the computer display. When this option is checked the touch operation is disabled for the Pause button and logging can be paused only by pressing computer key (for example <Enter>).

In case of a conicting Pause Key (lack of specied key in the computer) a soft keyboard can be opened and used at any moment. is option aects only sensitivity of the Pause button, other touch enabled functions are not aected.

After all the parameters in the System Setup dialog are updated click on the button OK or press ENTER key to accept the displayed settings. e program will return to the Main Screen. Updated settings will be written to the initial le and they will be given as default parameters in the subsequent System Setup dialog.

To return to original settings (state before this dialog was selected) click on the Cancel (or window X) button or press Esc key. All parameters will be reset to initial settings and the program will return to the Main Screen.

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4. GPS Port Setup & Monitoring

e GPS Port Setup dialog allows for enabling GPS input, and setting communication parameters for serial port associated with GPS input. GPS Monitoring window allows you monitoring the GPS output in terminal mode and to send NMEA commands to GPS receivers.

4.1 GPS Port Setup

After the Set Port for GPS button was clicked on (or executed from the keyboard) in the Main Screen the Set Port for GPS dialog window appears on the screen. is dialog allows you to enable and disable the GPS input, select serial port for GPS input, and to specify serial communication parameters matching GPS receiver settings. e dialog is presented below.

Description of Options and Parameters:

GPS Input

is option allows you to Enable/Disable a serial port for GPS input. When Disabled is chosen logging and monitoring screens will display message “GPS disabled” in place of GPS parameters.

e GPS Input can be Enabled even if there is no GPS system connected to the computer. In such case data le will contain proper sequence of EM61-MK2 readings without any GPS input.

Clicking on the down arrow next to the text box labeled GPS Input opens a drop-down box showing the available settings, or when the keyboard is used activate the text box by pressing TAB key and then by using up or down arrow keys select one of two available items: Enabled and Disabled.

EM61MK2win Data Logging System (DAS70-M2)

Serial Port

e number of serial port that is assigned to the GPS input. Available selections: COM1 to COM60. e program default is COM2. Communication parameters for the selected serial port can be determined in options described below.

is port must be dierent than the port specied in the System Setup menu (for EM61MK2), otherwise a message will be displayed and ports will have to be reassigned.

Clicking on the down arrow next to the text box labeled Serial Port opens a drop-down box showing the available ports, or when the keyboard is used activate the text box by pressing TAB key and then by using up or down arrow keys select one of available items.

Baud Rate

Specify Baud Rate for the output port, the selected value should match the Baud Rate of the GPS system, default is 9600. Available settings are: 4800, 9600, 19200, 38400, 57600, and 115200.

Clicking on the down arrow next to the text box labeled Baud Rate opens a drop-down box showing the available parameters, or when the keyboard is used activate this text box by pressing TAB key and then by using up or down arrow keys select one of available items.

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Parity

Select Parity for the output port, the parameter should much the Parity set in the GPS serial port settings. Available settings are None, Even, and Odd; default is N.

Clicking on the down arrow next to the text box labeled Parity opens a drop-down box showing the available parameters, or when the keyboard is used activate this text box by pressing TAB key and then by using up or down arrow keys select one of available items.

Data Bits

Specify Data Bits for the output port, the selected value should much settings in the GPS receiver, default is 8. Other available selection is 7.

Clicking on the down arrow next to the text box labeled Data Bits opens a drop-down box showing the available parameters, or when the keyboard is used activate this text box by pressing TAB key and then by using up or down arrow keys select one of available items.

Stop Bits

Specify Stop Bits for the output port, the selected value should much settings in the GPS receiver, default is 1. Available selections are 1 or 2.

Clicking on the down arrow next to the text box labeled Stop Bits opens a drop-down box showing the available parameters, or when the keyboard is used activate this text box by pressing TAB key and then by using up or down arrow keys select one of available items.

After all the parameters in the GPS Port Setup dialog are updated click on the button OK or press ENTER key to accept the displayed settings. e program will return to the Main Screen. Updated settings will be written to the initial le and they will be given as default parameters in the subsequent Survey Setup dialog.

To return to original settings (state before this dialog was selected) click on the Cancel (X) button or press Esc key. All parameters will be reset to initial settings and the dialog window will disappear.

EM61MK2win Data Logging System (DAS70-M2)

4.2 Monitoring GPS Receiver Output

After the Main Screen command button GPS Monitoring is clicked or executed by the keyboard the program will display the GPS Monitoring window in terminal mode. In this mode the screen is divided into three parts. e terminal window in the top portion of the screen displays the GPS receiver output. e middle portion labeled NMEA Command is used to display entered NMEA commands previously sent to the GPS receiver, and at the bottom, command buttons with available options (Pause/Go, Send, and Exit) is displayed. ese buttons can be clicked on, executed by TAB key and ENTER keys, or by using shortcuts (pressing underlined letter keys). is screen is shown below.

As soon as the EM61MK2win screen is in terminal mode and the GPS is streaming data, each message transmitted by GPS receiver will appear in the top portion of the display (the end may be cut o if an NMEA message is longer than screen). e display is updated with the frequency the GPS receiver outputs data. is allows you to recognize the GPS update rate and type of messages being sent by the connected GPS. In cases where the GPS data is not received by the logger a message NO DATA and current time will appear in the top window of the display, as shown below.

e message NO DATA is normally updated with a rate of 7 seconds. is may indicate the following: serial port number not correctly specied in Set Port for GPS dialog, GPS receiver not sending any data, and not working or not connected GPS receiver. If the message is updated more often than 7 seconds (i.e. every 1 or 2 seconds) or the display does not show legible characters, it is possible that the GPS is working correctly and is connected to the proper serial port, however communication parameters are not specied correctly. In most cases the Baud Rate or Parity must be adjusted.

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e NO DATA message may also appear if the GPS data are received correctly, but the GPS receiver was set to send data with a time interval longer than 7 seconds. In this case the NO DATA message will be displayed in between GPS messages. is indicates that the GPS is working correctly, however the operator should consider adjustment of the GPS receiver output update rate. Most high resolution geophysical surveys require positioning update of 1 or 2 seconds, and a 5 seconds interval can be used only when the survey is carried out at an even pace and along relatively straight survey lines.

e monitoring display can be stopped any time by using button labeled Pause. At that time scrolling of the GPS output will be stopped, and the button will be labeled Go. e next click (or keyboard action) on this button will activate receiving and display of GPS data.

e button labeled Send allows you to send a NMEA command to the GPS receiver. It is preferable if the GPS receiver parameters are set using the GPS manufacturer software or controller (GPS logger or panel keys). However, when the operator is familiar with NMEA protocol and structure of commands for a given GPS system, this function can be very convenient and useful when the update rate and enabling or disabling messages in the data stream is required.

After the button Send is clicked a dialog titled GPS Message is displayed and the beginning of the standard NMEA command, $PASHS, or the last entered command is displayed. After the entire NMEA command is typed in, click OK button or press the key <ENTER> to send the command to the GPS receiver. Clicking the Cancel button or pressing the <Esc> key will cancel the command and hide the NMEA Message dialog. An example of a command that will enable the NMEA message SAT is given in the below gure (it is assumed that the GPS receiver output serial port is A).

EM61MK2win Data Logging System (DAS70-M2)

After this command is received by the GPS receiver, the conrmation message will be send by the receiver ($PASHR, ACK*3D) and data stream will contain the message SAT if it is available in the connected GPS receiver.

Please note, that not every GPS system accepts and uses the same standard set of NMEA commands and messages. In addition, some GPS systems do not accept commands sent by the serial port at all. e conguration of these type of receivers can be updated only by the controlling device (usually GPS logger, controller, or the receiver panel keys).

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5. Display Options

After the Display Options button was clicked (or executed from the keyboard) in the Main Screen the Setup Display Options dialog window appears on the screen. is dialog allows you to enable and disable the display of each channel prole, specify color and thickness of proles, and select linear or compressed amplitude for proles. e dialog is presented below.

Description of Options and Parameters:

Visible

Color

To enable or disable displaying of each channel prole click on the corresponding button labeled Visible. Proles of all channels with checked buttons will be displayed during data logging.

Regardless of which channels are chosen to be displayed as proles, data for all four channels will be displayed in numeric form below prole display.

To change colour of each prole click on the corresponding button (with colour line) labeled Color (click to change). e following dialog titled Color will appear.

Select desired colour by clicking on a colour box (the selected colour box will be highlighted).

EM61MK2win Data Logging System (DAS70-M2)

Click on the button OK or press ENTER key to accept the highlighted colour. e Color dialog will disappear and the colour of the appropriate channel button will updated. To cancel colour selection click Cancel (X) button or press Esc key.

Thickness

Specify thickness of a prole for a desired channel by using one of four drop-down boxes labeled thickness. ickness of a prole curve is expressed in pixels. Available settings are: 1, 2, 3, or 4 pixels.

Clicking on the down arrow next to the text box (labeled by number of pixels) opens a drop-down box showing available selection (see Figure below). Select thickness by clicking on the desired selection. If keyboard is used activate text box by pressing TAB key (till the box is highlighted) and then by using up or down arrow keys select one of available items.

Prole Amplitude

is option allows you to select Linear or Compressed amplitude scale for proles. e compressed amplitude (squre root function) allows you to display the high dynamic range of the EM61-MK2 data in a legible way and it is recommended.

Clicking on the down arrow next to the text box labeled Prole Amplitude opens a dropdown box showing available parameters, or when keybord is used activate this text box by pressing TAB key and then by using up or down arrow keys select one of available items.

Please note, that readings in numeric form are always given in mV (linear scale) regardless of the Prole Amplitude selection. Further, graphic display in the compressed scale does not aect readings saved in the data le. Data are always written to le in original form.

After all the parameters in the Display Options dialog are updated click the button OK or press ENTER key to accept the displayed settings. e program will return to the Main Screen. Updated

settings will be written to the initial le and they will be given as default parameters in the subsequent Survey Setup dialog.

To return to original settings (state before this dialog was selected) click the Cancel (X) button or press Esc key. All parameters will be reset to initial settings and the dialog window will disappear.

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6. Logging Data

After the Logging button (in Main Screen) is clicked or executed by the keyboard, the program enters the logging session which contains three modes: Monitoring, Stand By and Logging. e program starts the logging session always in Monitoring mode. In this mode EM61-MK2 readings

and GPS parameters can be quickly examined and some functions (creating data le, nuling, QC coil check) can be performed. After a data le is created in Monitoring mode, the program switches to Stand By mode and allows access to Logging mode. In Stand By mode instrument output can be monitored and some survey and logging parameters can be changed, and Logging mode is used only to record data. Two modes Stand By and Logging are toggled by GO and Pause buttons.

6.1 Monitoring Mode

e Monitor mode allows initial inspection of the range of the instrument readings at a particular site, monitoring the instrument performance, quick inspection of the condition of the instrument battery, perform QC Coil check, and setting zero level of the instrument.

It is assumed that the instrument is turned ON prior to using this option. If the instrument is OFF or the instrument console is not connected to the computer the following message shown below will appear.

EM61MK2win Data Logging System (DAS70-M2)

Check the connection or turn the instrument ON and select the Monitor/Log option again.

Assuming that the instrument works properly the program will display the Monitor mode window and will start normalization session which lasts less than 10 seconds. After the normalization is nished the layout of the Monitor window is as follows (left - during Normalization, right - after Normalization):

e Monitor (as well as Stand by and Logging) window is divided into ve sections.

One line of text in the top section provides survey parameters (used in Stand By and Logging modes) and instrument information. In Monitor mode this section displays: instrument mode (4 or D), current display mode (Monitor, Stand By or Logging), and the EM61-MK2 battery level in Volts (following label B:). When ducial marker is pressed then label Marker is displayed.

e second, largest graphic section will be used to display proles during logging data. Numeric labels on the right side of prole window correspond to scale minimum (below the prole window) and maximum (above the prole window).

e remaining bottom section contains a window with current EM61-MK2 readings, three frames (File Parameters, Line Parameters, and GPS information), and command buttons located on the right side of the screen.

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If Mode 4 was selected on the instrument panel (it is displayed at the top of the screen) channels 1, 2, 3, and 4 will be displayed under prole window, and when Mode D was selected (for Top and

Bottom antennas) channels 1, 2, 3, and T will be given as labels in numeric window. e EM61MK2 readings are updated approximately 10 times per second during the monitoring session.

When GPS is Disabled in the Set GPS Port dialog a message GPS Disabled will be displayed. If the GPS port is Enabled and a working GPS receiver is connected to the eld computer the Monitoring screen will display GPS parameters, as presented below.

In the above Figure one line of the display is dedicated to show the GPS status. A label Positions will be used during data acquisition, it will provide the number of GPS positions saved in the data le. Below, two lines display the parameters describing the quality of GPS positions. A label DGPS (Dierential Global Positioning System) indicates that GPS readings are dierentially corrected in real time, while label AGPS (Autonomous Global Positioning System) indicates lack of dierential correction. On the right side of DGPS or AGPS label two green and white circles alternate. ese two circles should alternate colours with the frequency of GPS update rate (usually 1 second intervals). If the circles do not change colours for long periods of time it means that the GPS system is not working or that it is not connected to the eld computer. e next label PDOP with a value varying between 0 and 99.9 represents an index called Position Dilution of Precision (PDOP). is value is available only when messages both, GGA and GSA are received from GPS. e last label Sat and following number shows number of currently tracked satellites. Refer to section 4 (Set Port for GPS), Appendix B, and to GPS manuals for more information about GPS parameters. Two bottom lines of the frame give current Latitude and Longitude of the instrument position (datum WGS1984). Position is updated with frequency of GPS receiver stream.

EM61MK2win Data Logging System (DAS70-M2)

Six command buttons located in the right bottom corner of the Monitor window lists the program functions available directly in the Monitor mode. Available options are as follows: File (create data le), Scale Readings (change scale for EM61-MK2 readings in prole window), Exit (exits the Monitor mode and returns the program to Main Screen, Null (perform nulling function), Int. QC (internal QC-coi calibration), Ext.QC (external QC-coil calibration).

In case of any problems with instrument connection, battery failure, or accidental instrument Turn O a message "No Communication, trying" will be displayed in numeric values window. e message is highlighted by red background to alert operator as fast as possible. e EM61MK2win will try to re-establish communication and after the problem is corrected the program will start communication automaticaly. Alternatively, the Monitor mode can be stopped by clicking on the Exit button or executing this function by a keyboard. e Monitoring window with alerting message is shown below.

Description of Monitoring Mode Options

File (create data le)

e log data le can be created in any directory. e name of the le is given by the eld computer clock and it consists of month (2 digits), day (2 digits), hour (2 digits), and one alphabetic character A, B, C, etc. (If all letters during one hour are used use the Overwrite option). e Create Data File dialog is presented below.

e le name can be specied in the Create Data File dialog using the Windows standard interface procedure. e EM61MK2win data les cannot be appended.

Each data le in the eld computer (raw data le) has an extension name R61 and it is created in the directory specied in Create Data File dialog. e R61 les are created in the

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Null

instrument binary format. ese les can be also converted to ASCII format and processed in the Geonics DAT61MK2 program.

After the le is specied click on the button OK or press ENTER key to accept and create data le. e program will switch Monitor mode to Stand By mode and the data le will be displayed on the screen.

To cancel selection and return to Monitoring mode tap the Cancel (X) button or press Esc key.

To perform a null of the instrument click on the button labeled Null or execute this option using the keyboard (navigate to the button by pressing TAB key and when highlighted press ENTER key, or use shortcut - press key U). At this moment the computer takes 50 readings and calculates the instrument oset.

EM61MK2win Data Logging System (DAS70-M2)

e calculated oset is applied to all the readings that follow this operation. If needed, this procedure can be repeated several times until satisfactory results are obtained. However, there is no associated “Undo” function. If original values (without calculated osets) of the EM61-MK2 readings are needed, exit the EM61MK2 program and run it again. e EM61-MK2 instrument does not have to be turned OFF. Null operation can be also performed later during data collection.

Int.QC (Internal QC Coil Calibration)

e Internal QC coil calibration is described in detail in the EM61-MK2 Operating Instructions.

To start the calibration using Internal QC coil click on the key labeled Int. QC or execute this option by keyboard (navigate to the button by pressing TAB key and when highlighted press ENTER key, or use shortcut - press key I). is action begins by performing the automatic nulling which in this case is only in eect for the duration of the calibration process. It will not aect EM61-MK2 readings. After the nulling is completed (less than 5 seconds) the Internal QC coil Calibration window is displayed. All command buttons in the bottom right corner of logging windows are disabled during Calibration procedure.

When Calibration window is displayed please use keyboard keys (O or C) rather than a mouse to execute buttons labeled OK and Cancel. Clicking on buttons by mouse will work, however several mouse button clicks may be required.

After OK button is clicked (or shortcut key O is pressed) the window displays timer with elapsed seconds and EM61-MK2 readings. is display lasts for 60 seconds. During this time please follow the instructions provided on the EM61MK2win display.

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Internal QC coil calibration can end in the following four ways:

e process can be stopped by an operator at any time by clicking on the Cancel button or pressing shortcut key C.

e calibration may end by time out (60 seconds) if QC coil button was not pressed or this action did not activate QC coil. e following screen will then be displayed: After pressing any key the program returns to Monitoring window. To repeat Internal QC coil calibration please click on the Int. QC button again.

e logging program will determine if the instrument has passed test. If after activating the QC coil, the program determines that the reading is inside the standard values within +/- 10% tolerances then a message “CALIBRATION OK” will be displayed (see below).

Otherwise, if the program determines that the reading is outside of the test values range the corresponding message “CALIBRATION FAILED” is displayed.

EM61MK2win Data Logging System (DAS70-M2)

Regardless of the test result (OK or FAILED) the readings will be saved on screen. e program returns to Monitoring window after any button is tapped or ENTER key is pressed. en the Internal QC coil calibration process can be repeated.

Ext. QC (External QC Coil Calibration)

e External QC coil calibration is described in detail in the EM61-MK2 Operating Instructions.

To start the calibration using the External QC coil tap the button labeled Ext. QC or execute this option by keyboard (navigate to the button by pressing TAB key and when highlighted press ENTER key, or use shortcut - press key E). is action begins by performing the automatic nulling which in this case is only in eect for the duration of the calibration process. It will not aect EM61-MK2 readings. After the nulling is completed (less than 5 seconds) the External QC coil Calibration window is displayed (Figure below).

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After OK button is tapped (or shortcut key O is pressed) the window displays timer with elapsed seconds and EM61-MK2 readings. is display lasts for 60 seconds. During this time please follow the instructions provided on the computer display screen.

External QC coil calibration can end in the following four ways:

e process can be stopped by an operator at any time by tapping Cancel button or pressing shortcut key C.

e calibration may end by time out (60 seconds) if the External QC coil button was not pressed or this action did not activate QC coil. e following window will then be displayed (see below).

After pressing any key the program returns to Monitoring window. To repeat External QC coil calibration please tap the Ext. QC. button again.

EM61MK2win Data Logging System (DAS70-M2)

Otherwise, if the program determines that the reading is outside of the test values range the corresponding message “CALIBRATION FAILED” is displayed.

Regardless of the test result (OK or FAILED) the readings will be saved on screen. e program returns to Monitoring window after any button is clicked or ENTER key is pressed. en the External QC coil calibration process can be repeated.

Scale (New Scale for Prole Plot)

Selecting New Scale option allows the operator to enter new scale parameters for the prole plot. is option is available by clicking on the command button labeled Scale Rdgs. or directly from keyboard by using shortcut key <R>.

e Readings Scale dialog will be displayed. It contains two text boxes for Minimum and Maximum values of a new scale for prole plot. Current settings (minimum and maximum

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values) for the scale are displayed in the bottom right and top right corners of the plot area. After minimum and maximum values are specied click on the button OK or press ENTER

key to accept to accept new values and the prole plot area will be redrawn. To ignore an entry and return to Stand By mode click on the Cancel (X) button or press

Esc key, the dialog window will disappear and measurements can be continued.

Exit (exit Monitor mode)

After clicking on the Exit button (or executing this option using keyboard) the program immediately returns to Main Screen.

6.2 Stand By Mode

After data le is created in Monitoring mode the program automatically switches logging window to Stand By mode. is windows is similar to Monitor mode however it contains survey parameters (le name, survey line name, etc.) and dierent set of options represented by buttons displayed at the bottom of the screen. e logging window in Stand By mode in initial state (before any data is recorded) is presented below.

e main portion of the screen is occupied by the plot area which displays proles (see Figure below which shows Stand By mode after some data were collected). Readings in the plot area can be displayed in compressed amplitude scale, which corresponds to Square Root of the amplitude. In compressed amplitude scale 0 to 100 corresponds to 0 to 10,000 mV, and compressed range 0 to 200 corresponds to 0 to 40,000 mV. Plotting data in compressed amplitude allows you to show

EM61MK2win Data Logging System (DAS70-M2)

details in the low range of amplitude, as well as relatively good resolution in the high range of data on the small screen. Please note, that data displayed in the numeric form are always given in the standard, linear scale. e amplitude scale is divided by four or ve grey grid lines. In the case where the amplitude scale starts with a negative value, then the grid line corresponding to zero is always plotted as a thicker line.

Readings for Channels 1, 2, 3, 4 or T are shown in numeric form in a window below the plot area. Values of readings are labeled: Ch1, Ch2, Ch3, Ch4 or ChT. e program checks instrument mode continuously, therefore label Ch4 indicates mode 4 while label ChT corresponds to instrument mode D. EM61-MK2 readings (in numeric form) are updated in Stand By mode approximately 10 times per second. Proles in the plot area are updated only during Logging mode when data are actually saved in the data le.

A section of the window at the top of the screen contains one line of text displaying survey and instrument related parameters. ese are (from top left): logging mode Stand By or Logging, survey mode (Auto, Wheel or Manual), instrument mode 4 or D (labeled Mode:)), and EM61-MK2 battery level in Volts (labeled Battery:). When ducial marker is active a label Marker is displayed in this line.

File and Survey Line parameters, and GPS information are displayed in three framed boxes at the bottom of the Stand By window. File Parameters frame displays: name of the data le, total number of survey lines, total number of stations collected in the le, and total time of surveying. e Line Parameters frame contains: name of current survey line, current station, number of stations in the current survey line, and time of surveying current line. In the Stand By mode the station number will not change. Stations in the EM61MK2win program are incremented by station increment value after each reading is written to the data le.

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e third frame is dedicated to showing the GPS status. A number following the label Position provides the number of GPS positions saved in the current data le. In Stand By mode the number of positions is not incremented (it is updated only when GPS position is written to the le). Next two lines in this frame display parameters describing quality of GPS positions. A label DGPS (Differential Global Positioning System) indicates that GPS readings are dierentially corrected in real time, while label AGPS (Autonomous Global Positioning System) indicates lack of dierential correction. On the right side of DGPS or AGPS label two green and white circles alternate. ese two circles should alternate colours with the frequency of GPS update rate (usually 1 second intervals). If the circles do not change colours for long periods of time it means that the GPS system is not working or that it is not connected to the eld computer. e next label PDOP with a value varying between 0 and 99.9 represents an index called Position Dilution of Precision (PDOP). is value is available only when messages both, GGA and GSA are received from GPS. e last label Sat and following number shows the number of currently tracked satellites. Two bottom lines of the frame give current Latitude and Longitude of the instrument position (datum WGS1984). Position is updated with frequency of GPS receiver stream.

In case of any problems with instrument connection, battery failure, or accidental instrument Turn O a message "No Communication, trying" will be displayed in numeric values window. e message is highlighted by red background to alert operator as fast as possible. e EM61MK2win will try to re-establish communication and after the problem is corrected the program will start communication automatically. Alternatively, click on the Exit button or execute this command from a keyboard. e program window in Stand By mode and the alert message is shown below.

Several available eld options (in form of command buttons) are listed at the bottom right corner of the Stand By mode window. ey will be described in the following section 6.4.

EM61MK2win Data Logging System (DAS70-M2)

6.3 Logging Mode

e Logging mode is enabled by clicking on the button labeled GO (log data) or pressing the shortcut key G (or the <ENTER> key if button GO is highlighted) in Stand By mode. After this button is pressed the list of buttons at bottom of the screen will be replaced by one PAUSE button, label Stand By will be replaced by label Logging (at the top of the display) and data will be logged in the mode corresponding to the selected EM61-MK2 mode in the Survey Setup menu. All labels and parameters (with the exception of buttons representing Stan By mode options) are the same as in Stand By mode and they are described in the preceding section 6.2. e screen in Logging mode is presented below.

After the screen changes to Logging mode the current station (labeled Station:) is updated according to the station interval. Similarly, if GPS Input was enabled, total number of GPS positions (label Positions) in the data le is incremented every time (usually once a second) GPS position is written to the le. Prole curves (for channels selected in Display Options window) are updated after each reading is written to the data le.

In case of any problems with instrument connection, battery failure, or accidental instrument Turn O a message "No Communication, trying" will be displayed in numeric values window. e message is highlighted by red background to alert operator as fast as possible. e EM61MK2win will stop collecting data and will try to re-establish communication. After the problem is corrected the program will start communication automaticaly. Alternatively, click on the Pause button to return to Stand By mode. e program window in Stand By mode and the alert message is shown below.

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ere is only one option available in the Logging mode - pause logging. After a Pause button is clicked or Pause key (any key or other Pause Key selected in Logger Setup window) is pressed the recording is stopped and the Logging mode returns to the Stand By mode. In Stand By mode the EM61-MK2 data will be displayed with the update rate approximately 10 readings per second, however data will not be saved in the log le and prole curves will be not updated.

Exiting from the logging session and access to various eld options are available only from the logging window in Stand By mode.

6.4 Stand By Mode Field Options

Several eld options are available while the Logging window is in the Stand By mode. Options can be accessed directly from command buttons. Command buttons can be used by clicking on the desired button, or from the keyboard by pressing one of the shortcut keys (underlined characters on button labels) or by navigating using <TAB> key (sets button as a default button - default button is highlighted) and pressing <ENTER> key.

GO (log data) (start data logging)

Click on the GO button, or while using the keyboard press shortcut key <G> or if the button is a default button (highlighted) press <ENTER>. e logging window in Stand By mode will change to Logging mode and logging data starts immediately.

EM61MK2win Data Logging System (DAS70-M2)

New Line (New Survey Line)

e New Survey Line dialog is displayed (see Figure below). Selecting this option allows the operator to enter a new survey line number (name) and associated line parameters (Line Increment, Line Sequence, Direction, Start Station, and Station Increment). e new line number and associated parameters are prompted by the program based on parameters specied in the Survey Setup dialog.

At the top of the dialog the last survey line name and the last logged station are displayed. Default name for the new line is given based on the Line Increment parameter. e default Start Station, direction of the Station Increment, and Direction are determined based on Sequence selection. All these parameters can be overwritten by the user as described in the Survey Setup menu description (chapter 2).

After all the parameters in the New Line dialog are updated click on the button OK or press ENTER key to accept the displayed settings. e program will return to the Logging window in Stand By mode. Survey line name (Curr. Line) name and current station (Sta- tion) value will be updated and prole curves plot for former survey line will disappear.

To return to Stand By mode and current survey line settings (state before this dialog was selected) click on the Cancel (X) button or press Esc key.

New Stn. (New Station)

Selecting this option allows the operator to enter a new station number (within the same survey line). e New Station dialog is displayed (see Figure below on the left).

Current survey line, Start and Current station are displayed at the top of the dialog. e New Station can be entered in the provided edit box labeled New Station.

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Click on the button OK or press ENTER key to accept the new value. e program will return to the Logging window in Stand By mode. Current station (Station:) value will be updated and after data logging is activated the prole curves will have a small gap (two pixels) showing the new station entry (see Figure above on the right).

To return to Stand By mode and current survey line settings (state before this dialog was selected) click on the Cancel (X) button or press Esc key, the dialog window will disappear and measurements can be continued.

Comment (Field Comment)

Selecting this option allows the operator to enter a comment at any point of the survey. A maximum of 11 characters can be entered as a comment. e Enter Comment dialog is displayed.

Click on the button OK or press ENTER key to accept the comment entered in a text box of the dialog. e text of the comment is saved in the le with a corresponding time stamp and the program will return to the Logging window in Stand By mode.

To ignore an entry and return to Stand By mode click on the Cancel (X) button or press Esc key, the dialog window will disappear and measurements can be continued.

EM61MK2win Data Logging System (DAS70-M2)

Scale Rdgs (New Scale for Prole Plot)

Selecting New Scale option allows the operator to enter new scale parameters for the prole plot.

e Enter Scale dialog will be displayed (see Figure below on the left). It contains two text boxes for Minimum and Maximum values of a new scale for prole plot. Current settings (minimum and maximum values) for the scale are displayed in the bottom right and top right corners of the plot area.

After minimum and maximum values are specied click on the button OK or press ENTER key to accept new values and the prole plot area will be redrawn (see Figure above

on the right). To ignore an entry and return to Stand By mode tap the Cancel (X) button or press Esc

key, the dialog window will disappear and measurements can be continued.

Proles (new options for prole plot display)

After the Proles button was clicked or executed from the keyboard the Display Options dialog window appears on the screen. is dialog allows you to enable and disable the display of each channel prole, specify color and thickness of proles, and select linear or compressed amplitude for proles. e dialog is presented below.

Please refer to chapter 5 where this dialog and its parameters are described in detail. Click on the button OK or press ENTER key to accept updated display parameters. e

dialog will disappear and prole plot area will be redrawn in Stand By mode. To return to Stand By mode and current display options (state before this dialog was se-

lected) click on the Cancel (X) button or press Esc key, the dialog window will disappear.

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Null

During data collection (in Stand By mode) a conrmation message will be displayed (there is no such message if Nulling is performed in Monitoring mode) before actual operation is applied (see below Figure on the left).

EM61MK2win Data Logging System (DAS70-M2)

After above message is conrmed the program collects 50 readings and calculates the instrument oset.

e calculated oset is applied to all the readings that follow this operation (see Figure above on the right). If needed, this procedure can be repeated several times until satisfactory results are obtained. However, there is no associated “Undo” function. If original values (without calculated osets) of the EM61-MK2 readings are needed, exit the EM61MK2 program and run it again. e EM61-MK2 instrument does not have to be turned OFF.

Int. QC (Internal QC coil calibration)

e Internal QC coil calibration is described in detail in the EM61-MK2 Operating Instructions.

e Internal QC coil procedure in Stand By mode is identical as in Monitoring mode. e Please refer to section 6.2 (Description of Monitoring Mode Options) for more screen shots examples.

To start the calibration using Internal QC coil click on the key labeled Int. QC or execute this option by keyboard (navigate to the button by pressing TAB key and when highlighted press ENTER key, or use shortcut - press key I). is action begins by performing the auto- matic nulling which in this case is only in eect for the duration of the calibration process. It will not aect EM61-MK2 readings during later data collection. After the nulling is completed (less than 5 seconds) the Internal QC coil Calibration window is displayed. All command buttons in the bottom right corner of the logging window in Stand By mode are disabled during Calibration procedure.

Internal QC coil calibration can end in the following four ways:

e process can be stopped by an operator at any time by clicking on the Cancel button or pressing shortcut key C.

e calibration may end by time out (60 seconds) if QC coil button was not pressed or this action did not activate QC coil.

After pressing any key the program returns to Monitoring window. To repeat Internal QC coil calibration please click on the Int. QC button again.

e logging program will determine if the instrument has passed test. If after activating the QC coil, the program determines that the reading is inside the standard

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values within +/- 10% tolerances then a message “CALIBRATION OK” will be displayed. Otherwise, if the program determines that the reading is outside of the test values range the corresponding message “CALIBRATION FAILED” is displayed (see Figure below).

Ext. QC (External QC Coil Calibration)

e External QC coil calibration is described in detail in the EM61-MK2 Operating Instructions.

e External QC coil procedure in Stand By mode is identical as in Monitoring mode. e Please refer to section 6.2 (Description of Monitoring Mode Options) for more screen shots examples.

To start the calibration using the External QC coil click on the button labeled Ext. QC or execute this option by keyboard (navigate to the button by pressing TAB key and when highlighted press ENTER key, or use shortcut - press key E). is action begins by performing the automatic nulling which in this case is only in eect for the duration of the calibration process. It will not aect EM61-MK2 readings. After the nulling is completed (less than 5 seconds) the External QC coil Calibration window is displayed (Figure below).

When External QC Coil Calibration window is displayed please use keyboard keys (O or C) rather than a mouse to execute buttons labeled OK and Cancel. Clicking on buttons by mouse will work, however several mouse button clicks may be required.

EM61MK2win Data Logging System (DAS70-M2)

External QC coil calibration can end in the following four ways:

e process can be stopped by an operator at any time by tapping Cancel button or pressing shortcut key C. e calibration may end by time out (60 seconds) if the External QC coil button was not pressed or this action did not activate QC coil. After pressing any key the program returns to Monitoring window. To repeat External QC coil calibration please tap the Ext. QC. button again.

e logger will determine if the instrument has passed test. If after activating the QC coil, the program determines that the reading is inside the standard values within +/- 10% tolerances then a message “CALIBRATION OK” will be displayed. Otherwise, if the program determines that the reading is outside of the test values range the corresponding message “CALIBRATION FAILED” is displayed.

Exit (exit data logging)

During data collection (in Stand By mode) a conrmation message will be displayed (there is no such message if Exit is performed in Monitoring mode) before program exits logging window.

After above message is conrmed the program stops logging, closes data le and returns to Main Screen.

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7. View Data Files

is option allows you to view recorded data les. After the View Files button is clicked or tapped (or executed from the keyboard) in the Main Screen the View Data Files window will be displayed.

To open the data le click or tap on the button labeled File or execute this option using the keyboard (navigate to the button by pressing TAB key and when highlighted press ENTER key, or use shortcut - press key F). e Open Data File dialog is presented below.

EM61MK2win Data Logging System (DAS70-M2)

e le name can be selected in the Open Data File dialog using the Windows standard interface procedure. After the le is selected (highlighted) tap the button OK or press ENTER key to accept and display data le (to cancel selection tap Cancel (X) button or press Esc key). After the le is opened readings taken at the beginning of the rst survey line in the le are displayed, as shown below.

e main portion of the screen is occupied by prole plot of currently displayed survey line. Readings in the plot area can be displayed in linear or compressed amplitude scale. Amplitude display range (minimum and maximum value) is given by labels located at the right side of the plot area. Range of scale display can be changed by tapping the button labeled Scale Rdgs. e plot area is divided by four or ve grey grid lines. In cases where the amplitude scale starts with a negative value, then the grid line corresponding to zero is always plotted as a thicker line. Proles for each channel are plotted with colours and line thickness as selected in the Plot Options (see section Chapter 5).

A vertical bar (grey vertical line) indicates currently displayed station. e station is displayed in the window labeled Station Parameters (see description in the next paragraph) next to label Curr.Stn: and readings at this station for channels 1, 2, 3, and 4 (or T) are shown in numeric form below the plot area. e EM61-MK2 readings (in numeric form) are updated every time vertical bar is moved.

ere are three windows describing le, survey line, and station parameters. e left window labeled File Parameters lists le name, number of survey lines in the le, total number of stations, and total number of GPS positions if GPS positioning was used during the survey. e center window

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labeled Line Parameters contains parameters associated with currently displayed survey line: line name, number of stations in the current line, minimum and maximum stations. e right window labeled Station Parameters displays currently indicated station parameters: station number, reading mode, marker presence, and station increment within line.

To change the currently displayed survey line click or tap on the button labeled Select Line. A dialog labeled Select Survey Line will be displayed.

Tapping on the down arrow next to the text box labeled Line opens a drop-down box showing all available survey lines. When the keyboard is being used you can activate the text box by pressing the TAB key until the drop down box is highlighted and then by using Up or Down arrow keys select one of available lines (as shown above). After the survey line is selected and the button labeled OK is clicked on the dialog disappears and selected survey line is plotted. Please see next Figure where Survey Line 10 is displayed.

To change range of displayed values click on the Scale Rdgs button. A dialog labeled Reading Scale will be displayed. Specify new Minimum and Maximum values and then press OK. e plot area will be re-drawn with new range values.

EM61MK2win Data Logging System (DAS70-M2)

To shift the range of the displayed stations and to move the vertical bar indicating the currently displayed station, use the buttons located along the bottom of the View Files window. ese buttons can be activated by tapping or by pressing the keyboard keys. ey are divided in two groups: four buttons labeled Shift Prole Image are used to move image while four buttons labeled Shift Station Bar move grey vertical bar selecting current station and displaying its numeric values.

Shift Prole Image buttons:

button labeled |<< moves display to the minimum station of the currently displayed survey line,

button labeled >>| moves display to the maximum station of the survey line,

button labeled < moves display about 40% of the displayed range to the left,

button labeled > moves display about 40% of the displayed range to the right.

When using Shift Station Bar buttons:

button labeled << moves the bar 50 stations to the left,

button labeled >> moves the bar 50 stations to the right,

button labeled < moves the bar one station to the left,

button labeled > moves the bar one station to the right.

To exit the View Data Files window tap or click on the button labeled Exit. e program will return to Main Screen.

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Appendix A

A.1 Description of Data File in EM61MK2win (R61) Format

Each record contains 24 characters, including line feed at the end of each record.

Header of the le (contains six records starting with characters E, H, O, O, O, and O)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

M 6 1

H File Name Time Increment [s] (F7.3) 10

EM61MK2 - identication of program le W101 - version number (1.00, W - indicates le created by Windows CE program) Survey Type - GPS (if GPS Input Enabled) or GRD (grid) UT - unit type (0 = meters, 1 = feet) IT - instrument type

IM IP - not used (=1 xed) File Name - le name, maximum 8 characters Time Increment - time increment (Auto Mode) in seconds Oset - oset for indicated channels in mV IC QC coil value 10 - Line Feed character

M K 2

Offset for Ch1 (F9.2)

Offset for Ch2 (F9.2)

Offset for Ch3 (F9.2)

Offset for Ch4 (F9.2)

W 1 0 UT1 IT IM 10

Survey Type

QC coil value for Ch1 (F9.2)

QC coil value for Ch2 (F9.2)

QC coil value for Ch3 (F9.2)

QC coil value for Ch4/T (F9.2)

(0 =sensor 1x0.5m, 1 = 1x1m, 2 = 0.5x0.5m, 3 = HH61) instrument mode (0 =Auto, 1 =Wheel, and 2 =Manual)

QC coil calibration (=N not performed, <>N otherwise) value of QC coil calibration for indicated channels in mV

23 24

Header at the start of survey line (eight records starting with L, B, A, Z, O, O, O, O)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

Line Name (8 characters)

B Start Station (Format F11.2) 10

Dir

Z DDMMYYYY HH:MM:SS 10

Offset for Ch1 (F9.2)

Offset for Ch2 (F9.2)

Offset for Ch3 (F9.2)

Offset for Ch4 (F9.2)

Station Increment (Format F11.2) 10

EM61MK2win Data Logging System (DAS70-M2)

Former Offset for Ch1 (F9.2)

Former Offset for Ch2 (F9.2)

Former Offset for Ch3 (F9.2)

Former Offset for Ch4/T (F9.2)

23 24

Line Name - Line Name, maximum 8 characters Start Station - Start Station for the Line, format F11.2 Dir - Direction of the Line (E, W, N, or S) Station Inc. - Station Increment, format F11.3 Date - Date when Line was created, format DD-MM-YYYY Time - Real Time when Line was created, format HH:MM:SS Oset - Oset for indicated channels in mV at the start of Line Former Oset - Former oset for indicated channels in mV 10 - Line Feed character

Timer Relation

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

Computer Time (Format HH:MM:SS.sss)

Indicates relation between computer clock and the program timer. is record links timer in milliseconds and computer time (local time) in format HH:MM:SS.sss. is record is written to the le each time a new new line is entered.

Reading

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

1h 1l

I - indicator T, D, E, F, M, N, P, or Q. Each record representing reading starts with one of the following character, which indicates type of reading: T - Standard, Mode 4, channels 1, 2, 3, 4 D - Standard, Mode D, channels 1, 2, 3, T E - Hand Held, Mode 4, channels 1, 2, 3, 4 F - Hand Held, Mode D, channels 1, 2, 3, T M - Standard, Mode 4, channels 1, 2, 3, 4 +Marker N - Standard, Mode D, channels 1, 2, 3, T +Marker P - Hand Held, Mode 4, channels 1, 2, 3, 4 +Marker Q - Hand Held, Mode D, channels 1, 2, 3, T +Marker Gn - one character parameter (Hex format), contains Gain, see table of ranges at the end of this section. 1h - higher byte of the 2’s complement Hex number of Channel 1 1l - lower byte of Channel 1 2h - higher byte of the 2’s complement Hex number of Channel 2 2l - lower byte of Channel 2 3h - higher byte of the 2’s complement Hex number of Channel 3 3l - lower byte of Channel 3 4h - higher byte of the 2’s complement Hex number of Channel 4 4l - lower byte of Channel 4 5h - higher byte of the 2’s complement Hex number of TX current 5l - lower byte of TX current 6 - fraction of current (5h 5l), Hex number Time Stamp - time in ms from the Windows start (resets every 49.7 days) 10 - Line Feed character

2l2h

5h 5l 6

Time Stamp in milliseconds

Time Stamp in ms (10 digits)

23 24

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Comment

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

Comment (maximum 11 characters)

Time Stamp in ms (10 digits)

New Station

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

New Station (Format 11.2)

Time Stamp in ms (10 digits)

Nulling

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

Offset for Ch1 (F9.2)

Offset for Ch2 (F9.2)

Offset for Ch3 (F9.2)

Offset for Ch4 (F9.2)

Former Offset for Ch1 (F9.2)

Former Offset for Ch2 (F9.2)

Former Offset for Ch3 (F9.2)

Former Offset for Ch4/T (F9.2)

QC Coil Calibration

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

Offset for Ch1 (F9.2)

Offset for Ch2 (F9.2)

23 24

22 23 24

Offset for Ch3 (F9.2)

Offset for Ch4 (F9.2)

IC - II indicates Inrenal QC coil calibration, IE indicates External QC coil calibration.

GPS Data Message Records

Each GPS record (GGA Message) is broken in to several 22 characters strings and placed in the EM61MK2 data le which contains 24 characters records, including one character indicator and line feed at the end of each record. e GPS sequence starts at the line which contains character @ as the rst character, then records that contain continuation of the same message start with character #. e GPS sequence ends with a line starting with the character !. e last line contains logger time stamp in milliseconds for given GPS reading. A sample of the GPS message written in EM61MK2 format is given below.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

G P

x x . x , M , s

p p . p , s a a

, d d d m m . m

m m s s . s s ,

s s ,

a a a

m m m

a a

d d m

a a

, s

e GPS sequence may contain 4 to 6 records. Component of the GGA message may dier in length, however they are placed in the same number of columns. Refer to Appendix B (section B.2) for denition of each component of GGA data message.

EM61MK2win Data Logging System (DAS70-M2)

Time Stamp in milliseconds

A.2 Conversion Factors

EM61MK2 has four channels. Channels 1, 2, and 3 are common for Mode 4 and Mode D. Channel 4 in Mode D is named Channel T (it corresponds to Top coil).

e instrument response is converted to output voltage in mV for each sampling channel as given below.

Channel 1 to 4 - converted data DATA1 (to 4) - instrument output for each channel as recorded in logger RANGE - range is controlled by the EM61MK2, it can be 1, 10,

100

Standard Unit - Mode 4 (One Sensor 1 x 0.5 m or 1 x 1 m)

Channel 1=(DATA1 x 4.8333 x 2)/RANGE Channel 2=(DATA2 x 4.8333 x 2)/RANGE Channel 3=(DATA3 x 4.8333 x 2)/RANGE Channel 4=(DATA4 x 4.8333 x 2)/RANGE

Standard Unit - Mode D (Two Sensors 1 x 0.5 m or 1 x 1 m, Top and Bottom coils))

Channel 1=(DATA1 x 4.8333 x 2)/RANGE Channel 2=(DATA2 x 4.8333 x 2)/RANGE Channel 3=(DATA3 x 4.8333 x 2)/RANGE Channel T=(DATA4 x 4.8333 x 4)/RANGE

if coil is 1 x 0.5 m Channel T is further multiplied by a factor 1.114.

Hand Held Unit - Mode 4 (One Sensor)

Channel 1 = 0.902500 x (DATA1 x 4.8333)/RANGE Channel 2 = 1.363000 x (DATA2 x 4.8333)/RANGE Channel 3 = 2.026795 x (DATA3 x 4.8333)/RANGE Channel 4 = 3.018856 x (DATA4 x 4.8333)/RANGE

Hand Held Unit - Mode D (Two Sensors, Top and Bottom coils))

Channel 1 = 0.9025 x (DATA1 x 4.8333)/RANGE Channel 2 = 1.3630 x (DATA2 x 4.8333)/RANGE Channel 3 = 2.0430 x (DATA3 x 4.8333)/RANGE Channel T = 12.152 x (DATA4 x 4.8333)/RANGE

Further each channel is normalized by current following formula:

Standard Unit

Channel = Channel x 3000/Current

Hand Held Unit

Channel = Channel x 1800/Current

where, current is a value represented by 5h, 5l, and 6 in EM61MK2 data le (see section B.1)

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Table of Ranges Determined by the EM61-MK2 Microprocessor

HEX Ch1 Ch2 Ch3 Ch4

0 1 1 1 1 1 1 1 1 10 3 1 1 1 100 4 1 1 10 1 5 1 1 10 10 7 1 1 10 100 C 1 1 100 1 D 1 1 100 10 F 1 1 100 100 10 1 10 1 1 11 1 10 1 10 13 1 10 1 100 14 1 10 10 1 15 1 10 10 10 17 1 10 10 100 1C 1 10 100 1 1D 1 10 100 10 1F 1 10 100 100 30 1 100 1 1 31 1 100 1 10 33 1 100 1 100 34 1 100 10 1 35 1 100 10 10 37 1 100 10 100 3C 1 100 100 1 3D 1 100 100 10 3F 1 100 100 100

HEX Ch1 Ch2 Ch3 Ch4

40 10 1 1 1 41 10 1 1 10 43 10 1 1 100 44 10 1 10 1 45 10 1 10 10 47 10 1 10 100 4C 10 1 100 1 4D 10 1 100 10 4F 10 1 100 100 50 10 10 1 1 51 10 10 1 10 53 10 10 1 100 54 10 10 10 1 55 10 10 10 10 57 10 10 10 100 5C 10 10 100 1 5D 10 10 100 10 5F 10 10 100 100 70 10 100 1 1 71 10 100 1 10 73 10 100 1 100 74 10 100 10 1 75 10 100 10 10 77 10 100 10 100 7C 10 100 100 1 7D 10 100 100 10 7F 10 100 100 100

HEX Ch1 Ch2 Ch3 Ch4

C0 100 1 1 1 C1 100 1 1 10 C3 100 1 1 100 C4 100 1 10 1 C5 100 1 10 10 C7 100 1 10 100 CC 100 1 100 1 CD 100 1 100 10 CF 100 1 100 100 D0 100 10 1 1 D1 100 10 1 10 D3 100 10 1 100 D4 100 10 10 1 D5 100 10 10 10 D7 100 10 10 100 DC 100 10 100 1 DD 100 10 100 10 DF 100 10 100 100 F0 100 100 1 1 F1 100 100 1 10 F3 100 100 1 100 F4 100 100 10 1 F5 100 100 10 10 F7 100 100 10 100 FC 100 100 100 1 FD 100 100 100 10 FF 100 100 100 100

EM61MK2win Data Logging System (DAS70-M2)

A.3 Example of Data File in EM61MK2win (R61) Format

e Em61MK2 data le records are written in binary format, therefore the le may have dierent shape when displayed or printed, depending on particular video or pronter settings.

EM61MK2 W100GPS000 1 H 042320A 0.200 O 0.00E 0.00 O 0.00E 0.00 O 0.00E 0.00 O 0.00E 0.00 L0 B 0.00 AS 1.000 Z23042005 20:02:51 O 0.00 0.00 O 0.00 0.00 O 0.00 0.00 O 0.00 0.00 *20:02:51.000 4179829 @$GPGGA,020412.00,4336. #59410,N,07936.64856,W, #2,6,2,141.56,M,-35,M,5 #,119*55 ! 4287423 @$GPGSA,A,3,30,,,25,,20 #,,14,,06,,01,02.8,02.1 #,02.0*0D ! 4287441 Eÿ Ø `/^ ”N 4287673 Eÿ †/“ ”Q 4287879 C comment text 4287983 Eÿ ; G/yï ”O 4288089 Eÿ § h/¼þ ”W 4288279 @$GPGGA,020413.00,4336. #59408,N,07936.64857,W, #2,6,2,141.51,M,-35,M,6 #,119*58 ! 4288338 Eÿ ¶ 5/ # ”S 4288488 @$GPGSA,A,3,30,,,25,,20 #,,14,,06,,01,02.8,02.1 #,02.0*0D ! 4288419 Eÿ þ º/j ”O 4288677 Eÿ L t/k ”Q 4288885 @$GPGGA,020414.00,4336. #59411,N,07936.64846,W, #2,6,2,141.68,M,-35,M,6 #,119*5D ! 4289337

Eÿ 4 (/± • 4290288

@$GPGGA,020415.00,4336. #59411,N,07936.64845,W, #2,6,2,141.69,M,-35,M,7 #,119*5F ! 4290338

Eÿ È 1/Y • 4290496

@$GPGSA,A,3,30,,,25,,20 #,,14,,06,,01,02.8,02.1 #,02.0*0D ! 4290417 Eÿtr /F 4290687

Eÿkø/ à •

4290893

Eÿh/lÃ •

4291101

Eÿ2 Å/5Ñ • 4291293

@$GPGGA,020416.00,4336. #59420,N,07936.64848,W, #2,6,2,142.11,M,-35,M,4 #,119*5C ! 4291335 E

tsÝ3 • 4291502

@$GPGSA,A,3,30,,,25,,20 #,,14,,06,,01,02.8,02.1 #,02.0*0D ! 4291414 Eÿ*‚ b Œ ”Y 4291691 C building 4291793 E # *â ”V 4291900 E¸/D ”C 4292299

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Appendix B

B.1 Using the EM61MK2win with a GPS Receiver

e EM61MK2win program accepts input from GPS receiver that stream NMEA-0183 compatible data through their output port. e program uses two NMEA messages: GGA and GSA. e entire GGA message is used later by the DAT61MK2 program, while the GSA message is used only to display PDOP index on the logger screen.

e GPS system means (control device, receiver panel, or manufacturer software) must be used to set GPS receiver communication parameters, to specify frequency of GPS output, and number and type of NMEA messages sent by the GPS system output port. Any GPS system can send various NMEA messages. It is important to select only two messages (GGA and GSA) that are actually used by EM61MK2. e program will accept any GPS string sent by the GPS receiver, however it uses time to process GPS data that is not being used. erefore, selecting a larger number of NMEA messages for GPS output will result in slower data acquisition of EM61MK2win. Normally, the EM61MK2win running in a Windows XP based computer uses less than 100 ms to process and record GPS data from two NMEA messages, GGA and GSA.

Only message GGA is necessary to position EM61-MK2 data. If message GSA is not available in a particular system, the EM61MK2win will function and record position data based on GGA message. Lack of GSA message will result in PDOP index displayed as Not Available (N/A) on the logger display. Using message GGA alone will also result in slightly faster operation of the program. e speed can be further improved by setting higher Baud Rate (if it is supported by the employed GPS receiver) in Set GPS Port menu.

e EM61MK2win dedicates portion of the display and shows GPS status in a frame box. A number following the label Position provides the number of GPS positions saved in the current data le. Next two lines in this frame display parameters describing quality of GPS positions. A label DGPS (Dierential Global Positioning System) indicates that GPS readings are dierentially corrected in real time, while label AGPS (Autonomous Global Positioning System) indicates lack of dierential correction. On the right side of DGPS or AGPS label two green and white circles alternate. ese two circles should alternate colours with the frequency of GPS update rate (usually 1 second intervals). If the circles do not change colours for long periods of time it means that the GPS system is not working or that it is not connected to the eld computer. e next label PDOP with a value varying between 0 and 99.9 represents an index called Position Dilution of Precision (PDOP). is value is available only when messages both, GGA and GSA are received from GPS. is index measures the strength of satellite coverage for a given area. PDOP is aected by the number of satellites visible and their relative positions in the sky. e smaller the number of PDOP the stronger the satellite coverage is. When there are more than 5 satellites widely spaced visible, the PDOP is 4 or less. However, when there are less satellites visible, or they are unevenly spaced in the sky, PDOP values can be 6 or higher. In most cases, the PDOP in an open sky is less than 3, and most accuracies given for many GPS systems are given for this norm. Refer to GPS documentation and literature for more information related to error sources of GPS positioning. e last label Sat and following number shows number of currently tracked satellites.

Two bottom lines of the frame give current Latitude and Longitude of the instrument position (datum WGS1984). Position is updated with frequency of GPS receiver stream.

EM61MK2win Data Logging System (DAS70-M2)

B.2 Description of GGA and GSA Data Messages

GGA Data Message

e GGA message contains the GPS position information and it is the most widely used NMEA data message. is message takes the following form:

$GPGGA,hhmmss.ss,ddmm.mmmmm,s,dddmm.mmmmm,s,n,qq,pp.p,saaaaa.aa,u, +xxxx.x,M,sss,aaaa*cc<CR><LF>

Denition of GGA message component:

hhmmss.ss UTC time in hours, minutes, seconds of the GPS position ddmm.mmmmm Latitude in degrees, minutes, and decimal minutes s s=N or s=S, for North and South latitude dddmm.mmmmm Longitude in degrees, minutes, and decimal minutes s s=E or s=W, for East and West longitude n Quality indicator, 0 = no position, 1 = raw, no dierentially corrected

position, 2 = dierentially corrected position, 9 = position computed using almanac information

qq Number of satellites used in position computation pp.p HDOP = 0.0 to 99.9 saaaaa.aa Antenna altitude u Altitude units, M=meters +xxxx.x Geoidal separation (requires geoidal height option) M Geoidal separation units, M = meters sss Age of dierential corrections in seconds aaaa Base station identication *cc Checksum <CR><LF> Carriage return and Line feed

GSA Data Message

e GSA message contains active satellites and PDOP value. e GSA message is given in the following form:

$GPGSA,c1,d1,d2,d3,d4,d5,d6,d7,d8,d9,d10,d11,d12,d13,f1,f2,f3*cc<CR><LF>

Denition of GSA message components:

c1 Mode, M = manual, A = automatic d1 Mode, 2 = 2D, 3 = 3D d2-d13 Satellites used in position computation (range 0 to 32) f1 PDOP (range 0 to 99.9) f2 HDOP (range 0 to 99.9) f3 VDOP (range 0 to 99.9) *cc Checksum <CR><LF> Carriage return and Line Feed

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Geonics Limited EM61MK2win, EM61-MK2 Operating Instructions Manual

Specifications and Main Features

Frequently Asked Questions

User Manual