The file extension .dj means the file saved was intended to be sent to a DeskJet printer, and a file extension of .lj is a LaserJet printer and an extension of .tj is a ThinkJet printer file. The waveform files should have been saved as one of the viewable file formats such as .png or .bmp, or the waveform should have been sent to a connected printer. The only way to view the file contents now is to put the file on your PC and send the file to a connected compatable printer that recognizes DeskJet, ThinkJet or LaserJet formats.