The Trimble MT 1000 does a wonderful job of enhancing the tracking capabilities of Trimble instruments in highly reflective environments, but it does not always return as precise elevations as the user may require.

 Trimble has introduced another prism method that improves the vertical accuracy using this prism.

 It is the Semi Active mode, and is available in S series instruments running the latest firmware and Survey Controller 12.46 or Access 1.60 or later.

 This document uses a TSC2 running Survey Controller 12.46 for demonstration.

  Once your TSC2 is connected to your instrument, tap on the prism icon.


Tap on the center area of the prism information, where the target height is displayed.

 Tap on the pull down arrow in the Tracking mode box.

Select “Semi-Active” and tap on Accept in the lower right corner of the screen.

 The instrument will now track you using the active feature horizontally and when you take a measurement in STANDARD MODE, it will switch to the passive mode for the measurement which will give you a more precise elevation. 


Please note, this Semi Active mode only provides more precise elevations in the STANDARD MODE, so in topo or stakeout, you must switch to standard mode for this to work.