The 2SD2285 is documented in this 128 KB PDF. Its JIS part number, with the 2SD prefix, places it among NPN transistors intended for low-frequency circuits such as amplifiers, drivers and power stages. The catalogue labels it a schematic, but a part datasheet is the likely content, including ratings, curves and package dimensions. Use it to verify the pinout and the limits a substitute must meet when replacing a damaged device. Nothing beyond the part number is given, so check the marking and case style on the actual component.
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.