MARCH I/II
Frequently Asked Questions

If you have a a question or technical issue that is not addressed by this section, please contact us at support@cmtinc.com

 

MARCH I/II Frequently Asked Questions

General Information
Q1 How long can I collect data with a 2 MB RAM Disk?
Q2 How long should my March battery last in the field before it needs to be recharged?
Q3 How long should my March battery last before it needs to be replaced?
Q4 How can I tell if my March battery needs to be replaced?
Q5 What is the proper procedure for changing my March battery in the field?
Q6 What is the appropriate care and maintenance of my March battery?
Q7 Can I use an external antenna with my March?

Satellite Tracking
Q8 The Tracking Status Indicator always shows "ACQ" or "INS". How can I make it go to "N3Dx" mode?
Q9 Why does my March stay in "TRK" mode even when I am tracking 4 or more satellites?
Q10 Why does my March stay in "N2Dx" mode even when I am tracking 4 or more satellites?
Q11 I have an RTCM device (e.g., Coast Guard Beacon) attached to my March, but the Tracking Status indicator never goes into "N3Cx" mode. Why?

GPS Data Collection Issues
Q12 How can I collect a point feature (like a sign) in the midst of collecting a line (like a road) or an area (like a tract)?
Q13 How do I set up my March as a Base Station?
Q14 How can I get real-time differential correction in the field with my March?
Q15 How far can I be from a Base Station and still get accurate differential corrections?
Q16 Does rain affect data collection?
Q17 Why does my March go in an out of Navigating or Featuring mode when I am collecting data?
Q18 How accurate is the March at locating one's position?

Hardware Issues
Q19 How do I reset my March?
Q20 Why did my March hang up when I tried to open or create a Job?
Q21 Does my March need any maintenance if I don't plan to use it for a month or more?
Q22 I received a "Can't write file" error in the middle of my GPS Job. What should I do?
Q23 After using my March for a while under the sun, the display becomes too dark to read. What should I do?
Q24 I received a "Not enough memory. Part of it plotted" error when I tried to plot a Job. What should I do?
Q25 I received a "DISK FULL" message in the Featuring screen while storing a Feature. What should I do?
Q26 After I reset the March, I get a "Low Power" message. What should I do?
Q27 How do I reset the power meter to 0 after a run-down?

Formatting Issues
Q28 What are the signs that my March needs to be reformatted?
Q29 What is the drive configuration of the March?
Q30 How do I format my March?
Q31 How do I format the RAM Disk?
Q32 How do I "break out" into the OS from the splash screen?

 

 Q1  How long can I collect data with a 2 MB RAM Disk?

      
A March II with a 2 MB RAM Disk will store more than 16,000 point features, which is often enough for a day of work. However, you can fill a 2 MB RAM Disk with GPS data in about 5 hours when you continuously log a line or area feature. 

A March I with a 1 MB RAM Disk will store more than 8,000 point features. You can fill a 1 MB RAM Disk with GPS data in about 2.5 hours when you continuously log a line or area feature. 
    

 

 Q2  How long should my March battery last in the field before it needs to be recharged?

      
The field-replaceable March battery should give 4-5 hours of continuous use before requiring recharging.
      

   

 Q3  How long should my March battery last before it needs to be replaced?

      
Depending on several factors including usage and charging practices, a properly maintained March battery, on average, last up to one year before needing replacement.
        

      

 Q4  How can I tell if my March battery needs to be replaced?

      
If your March battery needs to be charged after less than 4 hours of use, you probably need to replace your battery. On average, the March battery should run for 4-5 hours on a full charge. 

Another indication that your March battery needs to be replaced is if after charging overnight, the March only works a short time before giving you the "LOW" message in the Tracking Status Indicator. 
         

   

 Q5  What is the proper procedure for changing my March battery in the field?

      

Normally, you would not remove the MARCH-II-E battery until after you have transfered your data to your PC. By removing the battery from the MARCH-II-E, you run the risk of losing your collected data if your MARCH-II-E is aged or not functioning properly.

Do not replace the MARCH-II-E battery in the field unless you are sure its mother board is still functioning properly and will retain the data for a few minutes while the battery is removed. Assuming the MARCH-II-E is able to keep the data intact, follow the procedure below: 

  Turn off the GPS receiver by pressing [ON] then [F2] 

  Turn off your March unit. (This step is very important).

  Replace your March battery .

 Turn the unit on . 
         

  

 Q6  What is the appropriate care and maintenance of my March battery?

      
Use the ACC-SMC-G3-M "Smart Charger" to charge your March battery. The smart charger should be connected to COM2. The smart charger will fully discharge and recharge the March battery in 10 hours or less. When the charging is complete, the smart charger will apply a trickle charge to your batteries. 
The March battery has a built-in charging jack and can be recharged independently using the optional ACC-RE21 recharger/adapter. If using the ACC-RE21, charge your battery for 16 hours when the power level is 20% or less. 

To view the power level of March battery, hold down the [ON] key for a moment then release it. This calls up the CMT-Field STATUS screen which displays the battery power levels in the "Batt Pack (%)" field.

If you will not be using your March for an extended period of time, save all data to a mass storage medium, then fully charge the battery before putting the system into storage. You should then charge the battery once every two weeks while the system is in storage. 

To prevent generating excessive heat, do not use the ACC-SMC-G3-M to charge a battery that has more than 50% remaining power. Also, do not keep the ACC-SMC-G3-M connected to your March for over 24 hours at a time.  If using the ACC-RE21, do not leave the charger connected for longer than 16 hours. If overcharged, the battery may be damaged and its life and performance may be reduced.
         

  

 Q7  Can I use an external antenna with my March?

      
Yes, an external antenna can be attached to a range pole or magnetic mount for use with the March. 

When using the external antenna, it is important that you install the cable properly using the strain relief system provided. If it is not installed properly, the antenna connector will bear the bulk of the strain and may break. 

To attach the external antenna cable, please do the following:

  Unscrew the strain relief attachment above the Input/Output ports of your March.

  Remove the connector of the integrated antenna from the antenna port. If the antenna connector is caught in the strain relief attachment, you may insert a small rod (such as a small screw driver) into the smaller hole in the strain relief to push it out.

  Push the external antenna connector straight into the antenna port. (It may "click".) This connector is quite delicate and needs to be handled carefully.

  Fit the channel on the inside of the strain relief attachment to the external antenna connector and the antenna cable. 

CAUTION: Failure to route the external cable through the channel may place excess stress on the connector and result in damage.

  Snap the two tiny pegs on the strain relief attachment into the two tiny holes in your March.

  Tighten the thumb screws to firmly connect the strain relief attachment with the March unit.

  Snap the connector of the integrated antenna into the larger hole in the strain relief attachment.
         

  

 Q8  The Tracking Status Indicator always shows "ACQ" or "INS". How can I make it go to "N3Dx" mode?

       
First, check your unit for the problems below: 

  Is the antenna connected? 
  Is the antenna unobstructed? 

Next, select "Setup" from the Main Menu and verify the following settings:

Is a correct approximate position entered in the SETUP RECEIVER screen (i.e., longitude E or W, latitude N or S)? If necessary, make any changes and press [F4](SAVE) to send this information to the March (the GPS receiver must be ON).

Is a reasonable Elevation Mask specified in the SETUP RECEIVER screen? The default value is 5. This is the recommended setting. If necessary, make any changes and press [F4](SAVE) to send this information to the March.

Does your unit have the correct UTC time and date in the SETUP TIME/DATE screen? You need to set the correct Local time and date, and the correct UTC TIME OFFSET (for example: the UTC time offset for Pacific Standard Time is -8 hours). If necessary, make any changes and press [F4](SAVE) to send this information to the March (the GPS receiver must be ON).

Then, confirm your GPS receiver has a current almanac. Follow the procedure below to check the almanac: 

Make certain that your GPS receiver is on, then, from the MAIN MENU, choose SETUP\RECEIVER. Scroll down with the Arrow keys to the SEND ALM? prompt and change it to "YES". Then hit [F4](SAVE) to send the almanac to the receiver. 

Finally, your March may need to be reset. Gently press the RST button (located on the March keypad) with a ballpoint pen. 

Double-check all of the above problem areas. If you are certain that your March is set up correctly, but it still will not track satellites, please contact CMT for assistance. 
         


 Q9  Why does my March stay in "TRK" mode even when I am tracking 4 or more satellites?

       
It is probably a settings issue. Check the following settings:

   From the Main Menu, select "Setup" and then choose "RS232 Input/Output". Then, from the RS232 setup screen, check the MODE setting for COM2. If it is set to "YES", change it to "AUTO". Press [F4](SAVE) to save the setting.

   Then, go to the Setup menu and choose Setup Receiver. From the Setup Receiver screen, check the ALT. CTRL field. If it is set to "3D ONLY", change it to "AUTO". 

Also check the DOP settings (PDOP, VDOP, HDOP). The default values are: PDOP>9, VDOP>8, HDOP>4. These are the recommended settings. Be sure to press [F4](SAVE) to save the settings.
         

   

 Q10  Why does my March stay in "N2Dx" mode even when I am tracking 4 or more satellites?

       
There are two primary reasons why this might happen: 

Reason #1:
From the Main Menu, select "Setup" and then choose "Receiver". If you have set the ALT. CTRL field in the SETUP RECEIVER screen to MANUAL, the March will always display the input altitude for your position. Therefore, the March does not generate an altitude based upon the GPS data it is collecting and always displays a status of N2Dx or F2Dx. Change the ALT. CTRL. setting to AUTO or 3D ONLY and press [F4](SAVE) to save the settings.

Reason #2:
If the VDOP level set in the SETUP RECEIVER screen is exceeded and the ALT. CTRL field is set to AUTO, the March will generate and log 2D data. 
         

 Q11  I have an RTCM device (e.g., Coast Guard Beacon) attached to my March, but the Tracking Status indicator never goes into "N3Cx" mode. Why?

       
There are three primary reasons why this might happen:

Reason #1:
The beacon receiver itself is not receiving corrections. Confirm that the "Lock" indicator displays a green light on the beacon receiver. If it does not, the beacon receiver may be out of reception range or have low battery power. Confirm that a fully charged battery is connected to the beacon receiver.

Reason #2:
The beacon receiver is attached to the wrong COM port on your March. It should be attached to COM2.

Reason #3:
The RTCM settings on your March are incorrect. Go to the Setup menu and select RS-232 Input/Output. The settings for COM2 should be as follows:
       BAUD> 4800   MODE> AUTO
       AGE LMT: 15 (SEC)
Confirm these settings and press [F4](SAVE).
         

 Q12  How can I collect a point feature (like a sign) in the midst of collecting a line (like a road) or an area (like a tract)?

       
Use the nested point feature. While storing a line or area, press [F2](PNT) in the Featuring Screen. Then, name the nested point, attach attributes and values, and press [F4](STORE). After you store the nested point a message comes up asking whether you want to continue storing the line or area or store another nested point.
         

 Q13  How do I set up my March as a Base Station?

       
Immediately after selecting "Collect Data" from the Main Menu, press F3 [BASE] in the Job Data screen . The Base Logging Mode allows 2 options, Base and BasePC. 

The Base mode will store the differential correction file in the I: drive of the March. After selecting Base mode, a screen appears showing the memory remaining. When you press [F1](START) the Start Time appears. [F1](STOP) stops the logging of base data. 

BasePC mode uses Kermit as a transfer protocol to store the base file onto a PC. Connect to your PC just as you would for standard file transfers. 
         

 Q14  How can I get real-time differential correction in the field with my March?

       
There are three main sources of real-time correction data: 

1. Coast Guard Beacons (DGPS) (See CMT's Beacon Receiver Package.) 
2. Subscription Service 
3. Broadcast from your own base station
         

 Q15  How far can I be from a Base Station and still get accurate differential corrections?

       
For 1 - 5 m accuracy, you must be within 300 miles of a base station. 
         

 Q16  Does rain affect data collection?

       
According to the US Department of Defense, GPS is an "all weather" technology. However, in cases where there is heavy canopy and snow or rain, GPS signals may be disrupted. The March itself is completely waterproof and will not be affected by rain, mud, etc., as long as the air valve is closed.
         

 Q17  Why does my March go in an out of Navigating or Featuring mode when I am collecting data?

       
The GPS signals may be blocked by obstructions (i.e., buildings, trees, etc.) causing the March to lose track of satellites. 

Also, be aware of how you hold the March; make certain that the antenna is not blocked by your body. If you are consistently having this problem, then you may want to consider an external antenna.
         

 Q18  How accurate is the March at locating one's position?

       
With differential correction, the horizontal accuracy is from 1-5 meters (95% of the time) when HDOP < 4. Without differential correction, 95% of the time your position is within 38 meters when HDOP < 4 (with SA off). 
         

 Q19  How do I reset my March?

       
Under normal conditions, you do not need to reset the March. However, you should know how to reset the machine in case there is a need to do so.

There are two ways to reset and reboot the March:

1. Hold down the [F3] key and then press the [ON] key. This is the equivalent of a [CTRL][ALT][DEL] sequence on a PC. The March will reboot itself.

2. Use the tip of a ball-point pen to press the RESET button located below the [F1] key. The March will turn itself off. Press [ON] to restart the CMT Field program. After some screen activities, you will see the MAIN MENU displayed.

Warning: Do not reset the March while you are collecting data in the CMT Field program. Doing so may irreversibly corrupt the associated data files. In case you get stuck in a program or in the March operating system, try holding the [F2] key down and pressing [ON]. Normally, this will terminate any running program and turn off the March. When you press the [ON] key again, the program will be restarted without any adverse effect on the data files.
         

 Q20  Why did my March hang up when I tried to open or create a Job?

       
Your I: drive may be full. Free up additional disk space by deleting old data files (after archiving them on your PC or a floppy disk).
         

 Q21  Does my March need any maintenance if I don't plan to use it for a month or more?

       
Yes. Your March battery requires recharging every month, even if the March is not being used. Failure to follow a regular recharging schedule is one of the major causes of data and formatting loss, and can permanently damage your battery. 

Click here for complete instructions on the care of your batteries during long-term storage.
         

 Q22  I received a "Can't write file" error in the middle of my GPS Job. What should I do?

       
This message may indicate that the March's RAM disk is full. 

First, press [ON] to go to the Status screen and check the available memory. It is likely that you will need to delete some old GPS jobs to free up disk space.
         

 Q23  After using my March for a while under the sun, the display becomes too dark to read. What should I do?

       
Press [SH] and then [ENTER] to call up the System Status screen. Then press the [F2](CONT) key to display the Contrast screen. Now press the DOWN ARROW key several times to lighten the display. Later, when you go into the office or a cooler area, you may use the UP ARROW key in the Contrast screen to increase the display contrast.
         

 Q24  I received a "Not enough memory. Part of it plotted" error when I tried to plot a Job. What should I do?

       
This is caused by memory fragmentation. You can solve this problem by resetting the unit. Then the unit will be able to display the plot for a larger Job.

If this problem persists, the Job you are trying to plot may contain too much data to be plotted completely.
         

 Q25  I received a "DISK FULL" message in the Featuring screen while storing a Feature. What should I do?

       
Quit the current Job and transfer the collected Jobs to PC-GPS. After you have transferred the Jobs to PC-GPS, delete the Jobs from the March.

Hold down the ON button to get to the system status screen and check the available memory. If it is only around 256 KByte, it means your MARCH-II-E is not properly formatted. Q30 and Q31 provide formatting instructions.
         

 Q26  After I reset the March, I get a "Low Power" message. What should I do?

       
When this message is displayed, the March does not have sufficient power to run the CMT Field program. You will need to charge or replace the battery. After you have charged or replaced the battery , you will also need to reset the March by pressing the RST key or using the F3-ON key sequence. 

If you do not reset the unit, the CMT Field application will act as though it is a basic unit without any options (such as NMEA, RTCM, PHASE). This means that the VERSION screen will not display a line that says: "OPTION: RTCM + NMEA". Also, in the "DEVICE" field in the INPUT/OUTPUT setup screen, the only option available will be "BARCODE". 

In other words, the options list is determined when the software is started. You cannot change it by charging the batteries or installing a new battery pack. You must reset the option list by resetting the March in order to access the options provided with your March unit.
         

 Q27  How do I reset the power meter to 0 after a run-down?

       
To reset the power meter to 0 after a run-down, follow these steps:

  ESC from the Main Menu to the Operating System.
  Go to the MACRO MENU (press [SH] and then [F4]).
  In the MACRO MENU, scroll over and highlight UTILITIES and press enter.
  In this menu, scroll down and highlight RSTBQ and press enter.
  It will ask you Y/N, and you need to go the MACRO MENU and select Y.
         

 Q28  What are the signs that my March needs to be reformatted?

       
If you perform a soft reset (i.e., hold down [F3] and press [ON]) and the March goes to the F: drive instead of starting the CMT Field program, you need to reformat your unit. 

This problem is likely to arise in the following situations: 
  • The March was allowed to sit for over a month without a battery recharge. 
  • The battery was replaced incorrectly. 
  • The battery was low, but the March was allowed to sit for a few days without being recharged.

 Q29  What is the drive configuration of the March?

       
The configuration of the unit is as follows:
  
DRIVE: SIZE OB or OPEN USUAL FORMAT 
A:  128K  OB  MEMORY
B:  128K  OB  MEMORY
C:  128K  OB  FILES 
D:  128K  OB  FILES (JOINED WITH C: )
E:  128K  OB  FILES
F:  128K  OB  OS (ROS)
I:  1MB (MARCH I)
 2MB (MARCH II)
 OB  RAM DISK
J:    OB  APPLICATION (MARCH GPS PROGRAMS)


         

  

 Q30  How do I format my March?

       
Reformatting the MARCH-II-E will erase all data from the unit. One way to reformat the unit is to remove the battery and let it sit for an hour or so then reinstall the battery. It should re-format itself (drive C: and drive I:) after it has started back up. If it doesn't, you can reformat drive C: by going to the MACRO MENU and following these steps:

  From March Operating System, press [SH] and then [F4] to call up the Macro Menu.

  Scroll down the list until you come to the word FORMAT. Highlight this word and press enter.

  Scroll down to "FORMAT C: 256" and press enter. Then hit GO and answer "Y". See also Q31.
         

 Q31  How do I format the RAM Disk?

       
The RAM disk is installed in Drive I. To format this drive, follow these steps:

  From the March Operating System, press [SH] and then [F4] to call up the Macro Menu.

  In the MACRO MENU, scroll over and highlight UTILITIES and press enter.

  In this menu, scroll down and highlight EDISK -d and press enter.

  Hit enter one more time in the next screen. The RAM disk is installed.

  Press [SH] and then [F4] to call up the Macro Menu.

  In the MACRO MENU, scroll over and highlight FORMAT and press enter.

  In this menu, scroll down and highlight FORMAT I: and press enter.
         

 Q32  How do I "break out" into the OS from the splash screen?

       
If you are unable to get to the operating system (i.e., the March is stuck in the splash screen ...."Please Wait....." ), use the following commands to break out:

  Hold down [F3] and hit [ON] to reset the March.

  While the autoexec file is running, hold down [F1] and hit [ON] to stop RS232 and EDISK from installing.

  You may need to repeat the steps above a few times to get the timing correct. You need to time the [F1] [ON] sequence just right to stop RS232 and EDISK from installing.
  



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