Geonics Limited EM38-MK2 User manual

EM38MK2
1745 Meyerside Drive, Mississauga, Ontario, Canada L5T 1C6
Tel: [phone] Fax: [phone]
E-mail: [email protected]
Geonics Limited
March, 2008
Version 1.15
EM38-MK2 DATA LOGGING SYSTEM
FOR FIELD COMPUTER Allegro CX Field PC
OPERATING INSTRUCTIONS

Table of Contents
1. Introduction ................................................................................................ 1
1.1 Program Requirements ......................................................................... 2
1.2 Installing EM38MK2 ............................................................................ 2
1.3 Data Files Transfer ............................................................................... 2
1.4 Running EM38MK2 Program ................................................................ 3
1.5 Main Menu......................................................................................... 3
Short description of Main Screen options ...............................................................4
2. Survey Setup ............................................................................................... 5
3. Logger Setup............................................................................................... 9
3.1 Bluetooth Connection of EM38-MK2 and Allegro CX ........................... 10
4. Set Port for GPS......................................................................................... 13
4.1 Monitoring GPS Receiver Output ........................................................ 15
5. Display Options ........................................................................................ 19
6. Logging Data............................................................................................ 21
6.1 Monitoring Mode .............................................................................. 21
Description of Monitoring Mode options..............................................................23
6.2 Stand By Mode.................................................................................. 24
6.3 Logging Mode................................................................................... 25
6.4 Stand By Mode Field Options ............................................................. 26
7. View Data Files........................................................................................... 31
Appendix A ....................................................................................................... 35
A.1 Description of Data File in EM38MK2 Format ...................................... 35
A.2 Example of File in EM38MK2 Format .................................................. 38
Appendix B ....................................................................................................... 39
B.1 Using the EM38MK2 with a GPS Receiver............................................ 39
B.2 Description of GGA and GSA Data Messages...................................... 40

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EM38MK2 Data Logging System (DAS70-CX)
1. Introduction
The EM38-MK2 data acquisition system (DAS70-CX) includes: an Allegro CX eld computer which
is Bluetooth enabled; EM38MK2 software for data acquisition (programmed for the Allegro CX MS
Windows CE.NET V4.2 operating system, specically); DAT38MK2 software for data processing;
and cables to connect the eld computer to either the instrument and / or another serial device.
Two models of the EM38-MK2 are available: EM38-MK2-1 and EM38-MK2-2. Providing similar
functionality, including the simultaneous measurement of both quad-phase (conductivity) and
in-phase (magnetic susceptibility) components, the dening difference between the models is the
number of included receiver coils: the EM38-MK2-1 includes one receiver coil with a 1 meter
transmitter / receiver intercoil spacing; the EM38-MK2-2 includes two receiver coils with 0.5 and
1 meter intercoil spacings. All references to the EM38-MK2 in this manual are applicable to
both of the models described above.
Program EM38MK2 acquires and records survey data from the EM38-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 real time in mS/m
(conductivity) or ppt (in-phase) in both graphic and numeric modes. In addition, the program al-
lows you to monitor the instrument output while data are not recorded. Program EM38MK2 also
continuously monitors the EM38-MK2 measured components (Conductivity and Inphase), dipole
mode (Vertical or Horizontal), state of ducial marker, as well as GPS signal quality parameters (if
connected to the system) without leaving the program.
The program allows the user to set the EM38MK2 into a specic instrument mode of operation:
AUTO or Manual modes. In AUTO mode readings can be automatically recorded in desired time
intervals, and in MANUAL mode readings are triggered manually by the operator. In AUTO mode
the program can record the EM38-MK2 components (Conductivity and Inphase) and one dipole
mode (Vertical or Horizontal) per station. In Manual mode any combination of dipole modes can
be taken at each station, and data can be averaged at up to 100 samples per reading.
The EM38MK2 will accept NMEA-0183 compatible data from a GPS receiver directly connected
to an Allegro eld computer. GPS data which are embedded in the EM38MK2 data le can be
processed later in the Geonics DAT38MK2 program. The connected GPS must be able to stream
NMEA-0183 compatible messages. The EM38MK2 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.
The EM38MK2 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). However direct GPS interface described above is highly recom-
mended as much more accurate and simpler (for data processing) method of GPS positioning.
Survey setup parameters are saved in a le, therefore they can be automatically used during subse-
quent data collection sessions.
The program has an option that allows you to view data les. Data les are saved to the programs
current data directory by default. Data le names, which can be set by the program based on the
computer clock or user specied, have extension names P38. Files can be transferred to a PC com-
puter using a memory card, or by a serial or USB port using the MS ActiveSync program.
Over 1,000,000 readings can be collected in the Allegro eld computer with a standard memory of
64 Mb. The maximum speed of data collection is approximately 21 readings per second assuming
1 Hz (or less) GPS input. In graphic display mode, a prole containing the last 135 data readings
is displayed for each component.

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EM38MK2 Data Logging System (DAS70-CX)
1.1 Program Requirements
To successfully use this software, you will need :
Computer
Field computer Allegro CX
Installed MS ActiveSync software (Version 3.50 or later) in desktop PC, or alternatively
PCMCIA memory card to transfer les.
Geonics EM38-MK2
The EM38-MK2 instrument with associated cables.
The EM38MK2 program for Allegro CX is stored on DAT38MK2 CD disk. All necessary initial
les (with extension names .INI) as well as data folder (DATA38MK2) are created in your eld
computer after the program is run for the rst time. Check that the le EM38MK2.EXE is included
in AllegroCX directory on the CD disk.
1.2 Installing EM38MK2
While using the Allegro CX the EM38MK2.exe le should be transferred from a desktop PC using
MS ActiveSync software and USB or serial cable provided by manufacturer. Optionally the program
can be transferred to an Allegro using the PC memory card.
It is recommended that the program be placed in non-volatile solid state storage. This memory is
represented in the Allegro by the C_Drive icon. In the My Computer on the Allegro, double-tap on
C_Drive icon, then folder C_Program Files will appear. The EM38MK2 program can be placed in
C_Program Files. Folders for data les should be also created in C_Drive, which is a safe area to store
data. The program creates folder DATA38MK2 which is the default folder for EM38MK2 les.
For more information about data storage options, refer to Chapter 3 of the Allegro CX manual.
1.3 Data Files Transfer
Data les are saved in the Allegro with extension N38. Transfer of les to desktop PC can be per-
formed with MS ActiveSync or by PC memory card. Data les with extension N38 are binary raw
data les. These les have to be converted to DAT38MK2 format with extension M38 (option
"Convert Files" in DAT38MK2). They can then be processed in the DAT38MK2 program.

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EM38MK2 Data Logging System (DAS70-CX)
1.4 Running EM38MK2 Program
To run the EM38MK2 program, locate it in the C_Program Files and double-tap its icon. The
EM38MK2 is a Windows CE based, button and dialog driven program designed to be simple to use.
Although the program fully supports touchscreen interface, keyboard entry may be convenient in
some eld applications. The EM38MK2 can be fully operated from the keyboard when touchscreen
functions are disabled by the user.
Options represented by the command buttons can be accessed by a single tap on the button. Buttons
can also be selected from the keyboard by using shortcuts (pressing key corresponding to underline
letter in button caption or by selecting button by pressing TAB and then execute by pressing EN-
TER. Shortcuts are the fastest way of accessing options represented by buttons.
Most options in the dialog windows are given in the form of text boxes and drop-down boxes which
can be accessed using touchscreen or by the keyboard. Each dialog window has a title bar with a
caption describing the dialog function and two buttons OK and X (Cancel). The OK button (or
key ENTER) conrms dialog selection. Tapping on the Cancel button (or pressing Esc key) closes
the dialog and returns to the initial selection.
1.5 Main Screen
The 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. The EM38MK2 Main
Screen is displayed below.

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These options are selected by using tapping buttons, or from keyboard using TAB/ENTER or
shortcuts indicated by underline label characters. The Main Screen buttons can be controlled with
the Down and Up arrow keys and <ENTER>.
Short description for each of the options follows.
Short description of Main Screen options
Monitor/Log
This option allows to monitor and log the EM38MK2 output. Monitor/Log screen starts
always in Monitor mode, and then after a data le is created Logging mode is available.
Monitor mode provides initial inspection of the range of the instrument readings at the
particular site, instrument calibration, monitoring the instrument performance, and quick
inspection of the instrument settings.
Survey Setup
The Survey Setup dialog will be displayed. All survey settings (survey line name, increments,
etc.) can be specied in this dialog.
Logger Setup
Dialog window that is associated with this option is used to set the instrument type, serial
port number or Bluetooth connection, and type of pause key.
Set GPS Port
The GPS Port Setup dialog allows to disable and enable GPS data acquisition. This op-
tion 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.
Display Options
The dialog which will allow you to specify colour and thickness of prole lines will appear.
This dialog provides also choice of gid lines for Conductivity or Inphase scale.
View Files
This option allows to review data les saved in Allegro.
Exit
This option will terminate the program execution.

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EM38MK2 Data Logging System (DAS70-CX)
2. Survey Setup
The Survey Setup dialog, presented below, contains several parameters which affect 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.).
Description of Options and Parameters:
EM38/2 Mode (EM38-MK2 Mode)
This option allows you to select the type of instrument survey mode. Set the EM38MK2 mode of
operation by selecting an item from the drop-down list box labeled EM38/2 Mode. Available modes
are: Auto and Manual. These modes of operation are described below.
Auto Mode
Readings will be triggered automatically at a specied frequency (see option
Readings/s).
In Auto Mode only one dipole mode (Vertical or Horizontal) can be selected.
Manual Mode
Readings will be taken only while the manual trigger (switch on the instrument
console or a handle) is pressed.
In Manual Mode any combination of dipole modes (Vertical, Horizontal or Both)
can be selected.
Please note that when Manual mode is selected options the option Reading/s
changes to option labeled Samples/Rdg.

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EM38MK2 Data Logging System (DAS70-CX)
Readings/s (Readings per second)
When this option is available (only in Auto mode) activate text box by tapping or using
TAB key and then enter desired value.
This parameter describes number of readings per second that will be taken. Any number
larger than zero can be entered, however the EM38-MK2 xed frequency of data output
is 21 readings per second. Therefore any entered value is rounded to the nearest possible
base frequency of the instrument, i.e. user specied frequency of 20 readings/s will result
in the effective data acquisition rate of 21 readings/s (every reading is logged), 9 readings/s
will cause the program to log at a rate of 10.5 readings/s (every second reading from instru-
ment output is logged), etc. At slower rates the difference between specied and effective
frequencies is negligible.
Samples/Rdg (Samples per Reading)
When this option is highlighted the editor is activated and you can enter desired value. The
edit box only accepts numerical positive values.
This parameter describes number of readings that will be taken after the trigger switch is
pressed. At the end of sampling time the logger will beep and an average value will be writ-
ten in to the le and plotted on the screen. During the sampling period interval data are
measured at approximately 20 readings per second. For example by specifying 10 samples,
0.5 second will be used at each station. The maximal sampling is 100 readings which cor-
responds to approximately 5 seconds at each station.
This option could be used to improve quality of data in areas of high industrial noise,
especially if the ground conductivity is relatively low (small response signal).
In cases when multiple sampling is not required (good signal to noise ratio) enter the value
0 or 1 and 1 reading per station will be taken.
This parameter is displayed only when the Manual Mode was selected.
Dipole Mode (instrument dipole mode)
Tapping on the down arrow next to the text box opens a drop-down box showing the available
settings, or when the keyboard is used activate the text box and then by using up or down
arrow keys select one of two or three available items: Vertical, Horizontal, and Both.
When Manual mode was selected three settings are available: Vertical, Horizontal, and
Both (see Figure below).

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EM38MK2 Data Logging System (DAS70-CX)
If Auto mode was selected then only two dipole modes are available: Vertical or Horizontal
(see Figure below).
Survey Line (survey line name)
Activate text box by tapping or using TAB key and then enter desired name (number) for
the survey line.
This is a user’s tag number/name for the prole line. The length of the name can not exceed
8 characters. The 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 tapping or using TAB key and then enter desired for the survey line
increment.
This parameter species the distance by which survey lines will be separated. This setting
will be used to determine number (name) of the next survey line.
Sequence
Tapping on the down arrow next to the text box opens a drop-down box showing the avail-
able settings, or when the keyboard is used activate the text box and then by using up or
down arrow keys select one of two available items: Alternate and One Way.
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.

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The choice of this parameter will affect the default start station, a signature of the station
increment, and line direction when parameters for the next survey lines is determined.
Direction (geographical direction of surveying along survey line)
Tapping on the down arrow next to the text box opens a drop-down box showing the avail-
able 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.
This parameter indicates the heading of the survey line, and is only used for information
purposes.
Start Station (start station of a survey line)
Activate text box by tapping or using TAB key and then entering the desired value for the
start station.
This parameter species the starting station number for the selected survey line. This 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 tapping or using TAB key and then entering the desired value for the
station increment.
This parameter species the station increment for the selected survey line. This 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 tap the button OK or press ENTER
key to accept the displayed settings. The 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 (settings before this dialog was selected) tap 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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EM38MK2 Data Logging System (DAS70-CX)
3. Logger Setup
This option allows you to specify several parameters in the logger. The Logger Setup dialog is pre-
sented below.
Description of Parameters:
EM38-MK2 Port
Displays the number of serial ports that are assigned to the EM38MK2. Available selections:
COM1, COM2, COM3, ... to COM12, with the exception of COM6 that is named as
Bluetooth and assigned for Bluetooth communication. Connection of EM38-MK2 and
Allegro via Bluetooth is described below in section 3.1. The program default is COM1.
Communication parameters for the selected serial port are set by the program, since the
EM38-MK2 operates at xed settings: Baud Rate (19200), Parity (N), Data Bits (8), and
Bit Stop (1).
This port must be different than the port specied in the Set Port for GPS option (see next
chapter), otherwise a message will be displayed and ports will have to be reassigned.
Select port number in the drop-down list box (see Figure below).
Units
Two selections are available: Meters or Feet.
Audio
Two selections are available: Yes or No. The audible click will be generated at each reading
when this option is enabled. At fast rate (above 10 readings/s) the sound may appear not
uniform, however this does not affect quality of data acquisition.

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EM38MK2 Data Logging System (DAS70-CX)
Pause key
Four selections are available: any key, Space Bar, Enter, and P This 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.
After all the parameters in the Logger Setup dialog are updated tap the button OK or press ENTER
key to accept the displayed settings. The 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 Log-
ger Setup dialog.
To return to original settings (state before this dialog was selected) tap Cancel (X) button or press Esc
key. All parameters will be reset to initial settings and the program will return to the Main Screen.
3.1 Bluetooth Connection of EM38-MK2 and Allegro CX
Data can be transferred from EM38-MK2 to Allegro CX by a wireless Bluetooth connection. To
select Bluetooth connection select Bluetooth item in EM38-MK2 Port list box (Figure below).

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EM38MK2 Data Logging System (DAS70-CX)
When Bluetooth connection is selected and Logger Setup is closed with OK button and other survey
parameters are specied, please proceed and tap (or execute by keyboard) option Monitor/Log. At
that time the EM38-MK2 must be ON.
After the button Monitor/Log is tapped the Allegro CX operating system starts detecting all devices
transmitting Bluetooth signal. The following window will be displayed.
When the progress bar in the above window ends a list of detected Bluetooth devices will be dis-
played. In most cases it will only be EM38-MK2, however if any other Bluetooth enabled device is
in range (for example cellurar telephone, GPS receiver, etc.) it will also be placed on the list.

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Please select Geonics EM38-MK2 by tapping the Select button. If Geonics EM38-MK2 is displayed
as the only item, the Select button must still be tapped or executed from the keyboard (in most cases
this button is highlighted, therefore pressing ENTER on the keyboard is sufcient). At this point
the operating system will gather the necessary information from the EM38-MK2 Bluetooth device.
No action is required, a windows shown below will be displayed for a few seconds.
After the above window disappears the EM38MK2 screen in Monitoring mode will be displayed
and the program can be operated in exactly the same manner as using the standard serial port.
Please note that during Bluetooth connection the instrument cannot be turned OFF. Even a mo-
mentary rotation of the switch labeled MODE to the position OFF will result in a connection
break and will end the logging mode. A new logging session will have to be started to continue
measurements.

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EM38MK2 Data Logging System (DAS70-CX)
4. Set Port for GPS
After the Set Port for GPS button was tapped (or executed from the keyboard) in the Main Screen
the Set Port for GPS dialog window appears on the screen. This dialog allows you to enable and dis-
able the GPS input, specify serial communication parameters matching GPS receiver settings, and to
monitor the GPS output in terminal mode (the bottom button). The dialog is presented below.
Description of Options and Parameters:
GPS Input
This 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.
The GPS Input can be Enabled even if there is no GPS system connected to the Allegro.
In such case data le will contain proper sequence of EM38-MK2 readings without any
GPS input.
Tapping 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: Enable and Disable.
Serial Port
The number of serial ports assigned to the GPS input. Available selections: COM1to
COM12, with the exception of COM6.The program default is COM2. Communication
parameters for the selected serial port can be determined in options described below.

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EM38MK2 Data Logging System (DAS70-CX)
This port must be different than the port specied in the Logger Set Up menu (for EM38-
MK2), otherwise a message will be displayed and ports will have to be reassigned.
Tapping 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.
Port COM6 is named Bluetooth and it is assigned for Bluetooth communication. This type
of connection can be used if GPS receiver is equipped with a Bluetooth option. Please refer
to GPS receiver manufacturer instructions. The procedure for detecting Bluetooth by the
Allegro will be the same as that described in the earlier section 3.1. Only one Bluetooth
connection can be used by the Allegro operation system, therefore if Bluetooth con-
nection is assigned for EM38-MK2 data acquisition the GPS receiver must then use
one of the physical serial ports. If Bluetooth communication is selected then all serial
communication parameters described below are ignored by the program since they are
adjusted automaticaly by the Allegro operating system.
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.
Tapping 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.
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.
Tapping 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.
Tapping 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.

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EM38MK2 Data Logging System (DAS70-CX)
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.
Tapping 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 Set GPS Port dialog are updated tap the button OK or press ENTER
key to accept the displayed settings. The 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) tap Cancel (X) button or press
Esc key. All parameters will be reset to initial settings and the dialog window will disappear.
To activate terminal mode which allows you to monitor GPS receiver output tap the button labeled
Monitor GPS Output, or when using keyboard select this button using TAB key and press ENTER.
The monitoring mode will work regardless of the GPS Input being Enabled or Disabled. This op-
tion is described in the following section.
4.1 Monitoring GPS Receiver Output
After the button Monitor GPS Output is tapped or executed by the keyboard the program will
display the screen in terminal mode. In this mode the screen is divided into three parts. The larg-
est, top portion of the screen displays the GPS receiver output. The middle portion shows that last
NMEA command sent to the GPS receiver (by default command shown in Figure below), and at
the bottom three buttons representing available options: Pause/Go, Send, and Exit. These buttons
can be tapped, executed by TAB key and ENTER keys, or by using shortcuts (pressing underlined
letter keys). This screen is shown below.
As soon as the EM38MK2 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 off
if an NMEA message is longer than screen). The display is updated with the frequency the GPS
receiver outputs data. This 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.

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EM38MK2 Data Logging System (DAS70-CX)
The message NO DATA is normally updated with a rate of 7 seconds. This 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.
The 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 mes-
sage will be displayed in between GPS messages. This 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.
The 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. The next tap (or keyboard
action) on this button will activate receiving and display of GPS data.
The 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 tapped 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, tap OK button or press the key <ENTER> to send the command
to the GPS receiver. Tapping 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).