HTDP is not intended to perform coordinate transformations between the various realizations of NAD 83 (e.g., between 2011, 2007, HARN, etc.). The NGS Coordinate Conversion and Transformation Tool (NCAT) should be used instead.

To transform coordinates in NGS Blue Book files (B-files), use this option rather than option 3 ("Transform observations to a specified reference frame and/or date").