According to the maker of Drdepth there should be a "son2xtf.exe" that converts the information according to "Humminbird sonar log files (.dat)', you must first place a copy of Humminbird's data converter utility 'son2xtf.exe' in the install directory of DrDepth. You can get this utility program from Humminbird (due to licensing this program can not be included in the DrDepth installer). With 'son2xtf.exe' in place, select your .dat file(s) to be imported (in this case R00005.DAT)." how do I find this son2xtf.exe?