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Professional Model

MX500 Digital Magnetometer.


The MX500 Digital Magnetometer is our latest design of  marine proton precession  magnetometer which uses one of the new generation of  ultra low power microprocessors to create an active tow-fish. The magnetometer consists of a tow-fish, a Control unit and display software. The tow-fish can be supplied with various lengths of cable up to 150 metres. The Control unit is housed in a small aluminium box and provides the interface between the tow-fish and the PC. It has connections for interfacing data from a GPS and an echo sounder, this data is then combined with the magnetometer data and transmitted to the PC over one COM port. The software application MXSurvey II runs on a standard PC or laptop running Windows and displays the data in graphical form while simultaneously storing it to memory. The data can be saved to hard disc for analysis later. 

Key Benefits

  • Digital telemetry for robust operation in the presence of other electrical equipment.
  • Built in depth sensor indicting  depth of tow-fish.
  • Tow cable with Kevlar strain member allows depressor weight to be attached directly to the cable for deep tow surveys.
  • Echo sounder interface allows graphical display of tow-fish and seabed depth on a PC.
  • Worldwide tuning option.
  • Large omi-directional toriodal sensor,  plus the ability to rotate the sensor inside the tow-fish to obtain maximum signal output throughout the world.
  • PC displays graphically the magnetic deviation, seabed depth, tow-fish depth and boat's position  all on one screen.
  • Full data logging plus real time rewind to see anomalies that have scrolled off screen.
  • Overlay known features on plotter chart, specials symbols for anchors, cannons, fisherman's snags etc.
  • PC computes tow-fish position from the boat's GPS position, coarse, layback and tow-fish depth.
  • Define on screen Survey Grids to maximise the chance of detection. Lanes just a few metres wide can be defined.
  • Export magnetic data or seabed depth data to 3D software drawing packages for better visualisation 

MX500 Digital Dual Sensor Magnetometer. 

The MX500 Digital Dual Sensor magnetometer system allows two tow-fish to be controlled simultaneously from one control unit. By towing the two fish out on booms, it is possible to increase the detection swathe significantly. The magnetometer consists of two tow-fish, each one is supplied with various lengths of cable up to 150 meters, a Control unit and display software. The Control unit provides the interface between the two tow-fish and the PC, it also connects data from a GPS and an echo sounder to the PC. All data is transferred to the PC using just one COM port. Our survey software package MXSurvey II displays the data in graphical form on the PC screen while simultaneously storing it to memory. The data can be saved to hard disc for analysis later. The advantage of the dual magnetometer system is that it makes  it possible to identify small magnetic  anomalies that could easily be missed using a single magnetometer system. In addition, temporal diurnal variations in the Earth's magnetic field caused by the sun can be easily identified and are not misinterpreted as possible targets. The dual system can be used in gradiometer mode with the tow-fish run side by side, inline or one above the other.

Key Benefits

  • All of the benefits of the MX500 Digital Magnetometer technology.
  • Built in depth sensors indicting  depth of both tow-fish simultaneously.
  • PC can display graphically the magnetic deviation from each tow-fish simultaneously, or as the difference (gradiometer) thus allowing the magnetometer to be used more effectively in areas containing magnetic rock.
  • PC computes each tow-fish position from the boat's GPS defined position, coarse and layback.
  • Tow-fish can be towed side by side to increase the detection swathe reducing survey time.
  • No false targets due to temporal dirunal changes in the earth's field. 

New Features added for 2008

  • Autopilot control for steering precise survey grids.
  • Optimum turning circle displayed on plotter when turning at the end of each grid lane.
  • Cable termination coupling so that depressor force is applied correctly to cable.
  • Survey boxes can be displayed on plotter to show areas already surveyed.

Professional version of MX500 Digital Magnetometer. 

Customers have been asking for a version of the MX500 magnetometer that can be used with industry standard survey software. In 2012 Planet Electronics Ltd launched the Professional version of the MX500 Digital  magnetometer system. This version computes the magnetic field in the tow-fish and outputs it to a PC as an NMEA ASCII character based sentence that is compatible with third party software. In addition, the professional version now has finer increments of the amplifier gain than the standard MX500 to provide better performance when used worldwide. The precession signal amplitude is also displayed while surveying to enable better monitoring of the tow-fish performance.

New Features added for 2012

  • New Professional version launched with interface to industry standard  survey software.
  • Professional version displays and records precession signal amplitude while surveying.
  • Finer digital gain increments for worldwide tuning


A low cost cable drum is available for cables longer than 50 metres. The cable drum is made of plastic so is ideal for use at sea. The cable on the drum terminates in a connector mounted on the spindle so that just the right amount of cable is paid out for each survey, the remainder remains on the drum. See our Accessories page for details.




Send mail to sales@planet-electronics.co.uk with questions or comments about this web site.
Last modified: September 06, 2012