When exporting the machine files and .cal file is present. Can this file be used in SCS900 in place of the .dc file?
Yes. Just change the file extension to dc.
If you copy the CAL file into a new SCS900 Project and start the software - it will be as if you have done all of the Observations of a Site Cal but have not completed it. You can add to the Site Cal or just Compute / Adjust the Site Cal and then Save it in SCS900 and it will become a DC file.
As Shea states a CAL is in the same format as a DC file, it just has a different extension. Rename the file to .dc will do the same thing. Bear in mind that your DC file now has all of the Control points as GPS and Site Coordinate Control Points as well if you do that.
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