At 578 KB, this 2N3903 PDF is considerably heavier than a typical one-part sheet, which may mean scanned pages or an extract covering several related devices, though the name does not confirm it. It is catalogued as a schematic. The useful content for repair is the pinout, case outline, absolute maximum ratings and characteristic data needed for testing and substitution. Verify the package marking on the board against the drawing, since the 2N3903 has been produced by more than one manufacturer.
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.