MAGNET Field: Correct base station

This guide will run through the steps to apply a base correction for GNSS surveys.

The Correct Base feature allows you to start a GNSS base receiver for RTK survey, without the need to set up that base receiver on a control point that is unreachable or obstructed. During or after the survey, you just need to measure an existing control point so MAGNET Field can compute the offsets. 

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MAGNET Field: Correct base station


Start by setting all the connections between the base receiver and the rover receiver. Find a full description in this article: MAGNET Field: Basic Training - GNSS configuration.

Connect to the base receiver

The General tab of the Connections dialog box allows you to change the type of the device to work and to select a job configuration before connecting to the device. 

  1. Select the Base radio button and click Connect.
  2. Select the base receiver in the Select Receiver dialog box.
  3. If a PIN has been defined for that receiver, enter it in the Device info field.
  4. Click Connect.

Start the base receiver

After establishing a connection with the base receiver, it is now possible to set up and start that same base station.

  1. From the main window, click Setup.
  2. Click Start Base.
  3. Enter the name of the Point where the base receiver is located. 
  4. Select the Code for the point from the drop-down list.
  5. Enter the antenna height, and set the type of height measurement (vertical or slant).
  6. Measure the current position by clicking the Measure button.
  7. Click the Start Base button to start the receiver as the base transmitting the correction data.

Rover receiver

Once the base receiver is started, it's now possible to connect to the rover receiver.

  1. Click Yes to open the rover Connections dialog box.
  2. The default selection is Rover.
  3. Click Connect.
  4. Select the rover receiver form the devices list.
  5. If a PIN has been defined for that receiver, type it in the Device info field.
  6. Click Connect.

LongLink Bluetooth

When you are working with a LongLink connection, base correction is automatically performed if the rover finds a single base. The LongLink tab allows you to select a base to reconnect if there are several bases found. The tab displays these buttons:

  • Disconnect breaks the current connection.
  • Refresh renews the list of available bases.
  • Connect initiates the connection with the selected base.

Note: The Connect and Disconnect buttons are in the same spot and change names accordingly.


MAGNET Field is now ready to be used for surveying.

  1. In the main window, click Survey.
  2. Click Topo to start your survey.

Correct Base

To access the Correct Base function, follow these steps:

  1. In the main window, click Setup.
  2. Click Correct Base.
  3. Select the Topo Pt either from Map, List, or Measure it on the fly.
  4. Select your Known Pt from Map or List.
  5. Click the green check mark Accept button.
  6. Click Yes to accept the offsets.