The complete MinGeo Cableless DIM system consists of a refurbished theodolite, equipped with a single-axis fluxgate sensor, together with the MinGeo DIM electronics, an Android tablet, and our proprietary DIM Android app. All the electronic components are powered with 5V DC. A single-axis fluxgate sensor is fixed on the telescope and connected to our proprietary MinGeo DIM electronics.

The overall simple construction of the system and low power consumption of the electronics allowed us to mount the electronics in a small box on the telescope. This way, everything moves together with the sensor during the measurement procedure, and any magnetic moment is canceled out. Measurement data are transmitted to a tablet via BT to ensure easy operation and data recording/processing. Measurement is initialized by a small non-magnetic remote controller.

A 10" tablet is used to display and store measurement data together with other attributes, such as session identifier, GPS time, battery status of the magnetometer and that of the tablet, actual and next telescope positions, BT connection quality, etc. All data are stored in the tablet, and the data can be easily downloaded. A bar display and an audio signal both help the operator to find the measurement range.

Benefits:

• Trouble free theodolite rotation without sensor cable
• Automatic calculation of magnetic meridian
• Template manager for observation
• Preliminary data processing
• High accuracy in absolute magnetic observation
• Less observational error due to data storage
• A bar display and/or an audio signal with ± 3000 nT range on 10" tablet to easily find the null positions
• ± 200 nT magnetic range
• MinGeo 10 Cableless DIM provides more accurate angle measurement than MinGeo 20, however the measurement time is longer, since the horizontal and vertical angles cannot be read simultaneously
• MinGeo 20 Cableless DIM provides sufficient precision for absolute magnetic observations in short time, since the horizontal and vertical angles can be read simultaneously
  

Applications:

• Earth's magnetic field Measurements
• Reference measurements of the variometers at observatories
• Repeat station survey
• Compass & rangefinder calibration
• In field referencing in oil and gas exploration

DIM Android application

• Manual angular data recording
• Fluxgate magnetic output & UTC time from GPS are saved by the app
• Autofill for predictable angles at 'null' and 'residual' methods
• Automatic Magnetic Meridian Calculation
• Output angular formats: 'gon' or 'dms'
• Enables manual input of scalar magnetometer data
• GSM90 or GSM19 scalar magnetometer can be connected
• Azimuth Geographic True North calculator

Main technical parameters:

• Angular measuring accuracy

  	Theo-10 *	Theo-20
  Circle division	0.2 gon (20')	1.0 gon (1º)
  Micrometer scale division	0.2 mgon (1")	0.01 gon (1')
  Angular reading estimation	0.02 mgon (0.1")	2 mgon (0.1')
  Mean sq. error of direction measured face left/face right	± 0.3 mgon (± 1.0")	± 1.0 mgon (± 3.0")

  * Theo-10 - temporary stock shortage may occur

• Magnetic resolution 0.1 nT
• Magnetic measurement range: ± 200 nT
• Fluxgate sensor alignment: better than ± 3' = ± 55.6 mgon
• Instrument offset: better than ± 10nT
• Instrument operation time 10+ hr
• Operating temperature: 0 ºC to +40 ºC
• Achievable measurement accuracy: maximum low frequency error between absolute magnetic observations ± 2.5 nT

Standard accessories:

• Android 10 tablet with DS app, GPS, 10" display, Bluetooth 4.0 BLE
• Remote controller
• Steep sighting prism set for the telescope and microsccope
• Sunfilter for telescope
• Simple nonmagnetic servicing tools
• Plummet
• Universal charger (mains/5V DC)
• Plastic transport case
• Certificates and manuals on tablet

Optional accessories:

• Diagonal eyepiece for microscope (at around the Equator)
• Wooden steel-free tripod (for field use)
• Industrial rugged tablet

Dimensions

• Height of instrument: 33.4 cm
• Container: 55x65x35 cm
• Tripod: 16x16x160 cm

Weight

• Instrument: 4.8 kg
• Instrument in plastic case: 9.2 kg
• Tripod: 5.6 kg

Pictures of MinGeo Cableless DIM