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Dual Antenna VBOX Speed Sensor - Quick Start Guide

Product Code Quantity Description



VBOX Speed Sensor unit Dual Antenna (100 Hz)



GPS/GLONASS antenna with SMA connector (4 m)
Note: You may have to order additional cables separately

You can find the full specification for your VBOX Speed Sensor here.


Please register your VBOX Speed Sensor so that Racelogic can continue to provide you with notifications about the latest software releases and firmware upgrades for your Racelogic product and offer technical support.

Register your device here.


Your VBOX Speed Sensor is ready to use out of the box, applying the default settings. However, you can change the setup by using the VBOX Setup Software to edit the settings written to the Speed Sensor.

To read more about how you can configure your Speed Sensor, see the VBOX Speed Sensor Configuration chapter. 


The VBOX Speed Sensor should be securely mounted inside the vehicle, level with the ground. There are holes in the ground plate that can be used to fasten the Speed Sensor to a suitable location in the vehicle. Make sure that the surface with the LEDs and pin information is up. 

Antenna Placement

Even though installing and using the Dual Antenna VBOX Speed Sensor is intended to be fast and simple, you must pay careful attention to the placement of the antennas. 

Antenna A is the primary antenna, from which all calculations are based. You should place the primary antenna relative to where you wish to make your measurements from.  For example, If you wish to make measurements from the centre of the vehicle, you achieve this by placing the primary antenna at the centre of the vehicle or translating the position using the slip angle translation function in VBOX Manager.

Where possible, you should place the antennas on a level plane. The measured distance between the antennas should be the 2D distance between the antennas as viewed from above. It is not the straight-line distance between the antennas, regardless of the mounting angle.

Use the supplied tape measure to ensure accurate antenna separation.


It is essential that the separation between Antenna A and Antenna B is exactly the same as the separation value set for the Speed Sensor via the VBOX Manager or the VBOX Setup Software. If the distance is incorrect, your data may be inaccurate or not captured at all.





Connect the serial plug to the computer's serial port with an RLCAB093 loom – you can also do this via a serial > USB converter if required.

Note: The RLCAB093 loom is not supplied with the VBOX Speed Sensor, but is available to purchase separately.


The VBOX Speed Sensor can be powered from a wide range of voltage sources including a Vehicle Cigar adapter, a Racelogic Li-ion battery pack or other sources provided by the user. The maximum operating voltage input must not exceed 30 V DC. Failure to observe this limit could result in damage to the speed sensor.


  • There is no power cable supplied with the VBOX Speed Sensor, but this is available to purchase separately.
  • During extended use, the Speed Sensor's case may become hot. This is normal, however, it is good practice to mount the VBOX Speed Sensor in a position where it has sufficient airflow around the case.

GPS Coldstart

You may need to perform a GPS Coldstart when:

  • The GPS/GNSS engine has locked up.
  • The Speed Sensor is struggling to acquire satellite lock

A GPS coldstart forces the GPS engine to reset its downloaded almanac of current satellite positions. This can be useful if the Speed Sensor is having trouble locking onto satellites, which typically occurs if the unit has not been used for several weeks or if it was last used a long distance (over one thousand miles) away from the current location.

After performing a GPS coldstart, leave the Speed Sensor powered up in a static location where the antenna has an unobstructed view of the skies until the ‘GPS’ LED becomes solid green.

Find the instructions for performing coldstarts here


The VBOX Speed Sensors have default settings applied so that you can use them straight out of the box. You can, however, also configure the settings for your Speed Sensor, by using the VBOX Setup software, which you can download here. Find more information about how to configure your VBOX Speed Sensor here in the VBOX Speed Sensor User Guide.

VBOX Speed Sensor Digital Input

You can use the Digital Input on the VBOX Speed Sensor to program the position of virtual lines which lets you set Start/Finish and Split lines. Racelogic can provide different triggers and switches to use with this feature. For more information on available Digital input accessories, click here.

Read more about how you can configure your VBOX Speed Sensor to set the function of the Digital Input to either Lap pulse or Brake Trigger mode here.

For Slip and Pitch measurements

Required equipment (All supplied as standard unless specified):

  • VBSS100SL                                                                                         
  • Connecting Loom (RLCAB093-C)                                               
  • VBOX File Manager + RLCAB005-C
  • 2 x GPS & GLONASS antenna (RLACS156)
  • Tape measure
  1. You need to mount your VBOX Speed Sensor flat inside the test vehicle. Failing to do so will affect the accuracy of the calculated slip channels.
  2. Mount the GPS/GLONASS antennas on the vehicle roof, in-line with the direction of motion and clear from any obstructions (see image below). For normal operation, place the primary antenna (Socket A) at the rear of the car, and the secondary antenna (Socket B) at the front. All measurements are made from the primary antenna.
  3. Make sure the antennas are rotated so that the wires exit in the same direction.
  4. Accurately measure the separation distance to the nearest 5 mm. To achieve best accuracy, measure from the point where the cable exits the antenna.
  5. Power up your VBOX Speed Sensor.
  6. Connect VBOX Manager to the Speed Sensor via the Lemo CAN connector on the RLCAB093-C.
  7. Use VBOX Manager to go into VBOX->DUAL ANTENNA->SEPARATION and enter the separation distance between the antennas.
  8. Give the unit time to acquire a full satellite lock. The number of satellites in view is indicated by the SATS LED; the total of green flashes indicates GPS count, while an orange flash indicates the GLONASS satellite count. If you have not used the Speed Sensor for a long time, or the location where it is being tested has moved,you may have to perform a GPS Coldstart. You must use the VBOX Setup Software to do this

For Slip and Roll measurements

Follow the steps in the ‘Slip & Pitch measurement’ guide, but mount the antennas 90° to the true heading of the vehicle. The primary antenna (Port A) should be on the left-hand side of the roof. The recommended minimum separation between the antennas is 0.5 m on a level plane, just note that the greater the separation distance, the better the accuracy will be.

Use the VBOX Manager, go into VBOX->DUAL ANTENNA-> and tick ‘ROLL MODE’.

Go into VBOX->DUAL ANTENNA->SEPARATION and enter the separation distance between the antennas.

Try to avoid placing the antennas close to the edge of the roof as this may result in the poor dual lock. This is because reflections from the ground will disturb the signals.

To get a useful slip angle in Roll mode, you will need to follow the slip translation guide. The slip angle is calculated from the primary antenna position which in roll mode is off-centre and will give inconsistent measurements. Translating this position back to the centre of the car will make the slip measurement consistent when turning both ways.

Using the Dual-antenna Speed Sensor

You can read more about using your Dual Antenna VBOX Speed Sensor in the Dual-antenna VBOX Speed Sensors Knowledgebase Article.    

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