Hi abeach,
Yes, it is possible. All the Channels and their properties and all the Groups and their properties from all the separate TDM files would be present in the new (big) TDM file. But that new TDM file would only have one Root (File level) with its set of properties. If you care about preserving the Root properties from all the separate TDM files, you should think about where you want to write that information in the new (big) TDM file-- typically either as duplicated properties at each respective Group or as differently named properties at the new Root level (Author_File1, Author_File2, etc.).
As to how to carry out the merging, this can be done with either DIAdem or LabVIEW, and the process is conceptually the same. You just load all the TDM files that you want to merge, make any property adjustments you need to make, then save the total data set out to a new TDM file.
Brad Turpin
DIAdem Product Support Engineer
National Instruments
