PDF document for the 2SK1530, filed under schematics although the name is only a semiconductor part number. In the Japanese JIS designation system the 2SK prefix marks an N-channel field-effect transistor, so this 225 KB file is most likely a manufacturer datasheet rather than a board drawing. Technicians use such a sheet for pinout, voltage and current ratings, on-resistance and package outline when testing or substituting the part. Any PDF reader opens it; check the marking on the component body first.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @cyberlanelectonik. Enginerys does not host this file.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.