PDF of 210 KB for the 2SA817 transistor, catalogued as a schematic but named only by the component number. Under JIS conventions 2SA denotes a PNP bipolar transistor, so the content should be the datasheet with maximum ratings, electrical characteristics and package drawing. A separate file covers the 2SA817A variant, so compare both if the marking on your part carries a suffix. Use the data to confirm pinout, verify ratings against the circuit's supply and current, and pick a compatible PNP replacement when needed.
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.