The name of this 421 KB PDF carries just one token, 2SK2836, a JIS-format number for an N-channel FET. Despite the schematic label, the content is most likely the component datasheet. It supports routine repair tasks such as confirming gate, drain and source positions, checking breakdown voltage against the circuit supply, and evaluating replacement parts. No revision, maker or package is given in the name, so cross-check the physical part marking and footprint before ordering or fitting a substitute.
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.