Open the job file and switch to 3D
View Mode. 
From the Ref menu, choose the desired surface for export.
TTM (Trimble) and TN3 (Topcon) are tri-mesh files. AGTEK creates these files using the Export command from the File Menu in 3D View Mode.
Choosing the Surface to Export
Open the job file and switch to 3D
View Mode.
From the Ref menu, choose the desired surface for export.
The surface that displays as the Ref Surface is the one that is exported.
Select Save As from the File Menu. The Save As window displays.
Choose either TN3 or TTM for the desired file type. The name defaults to the current job name with either the .tn3 or .ttm extension. Change the name if desired.
Press the Save button to save the tri-mesh file.
Also see: Opening TTM and TN3 Files