Datasheet-style PDF for the 2N5089, listed in the schematic category at 97.4 KB. The name gives just the JEDEC part number, with no maker or revision stated. Repair technicians consult such documents to read the pinout diagram, electrical characteristics tables and safe operating limits, which helps when testing a suspect device with a multimeter or choosing an equivalent. Any PDF viewer opens it; check the package drawing against the component on the board before soldering in a replacement.
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.