PDF documentation for the 2SK772, size 77.7 KB. Within the Japanese JIS numbering scheme, 2SK identifies N-channel field-effect transistors, so the content is most likely a manufacturer datasheet rather than a circuit diagram. It provides pinout, ratings and characteristics needed to test the part, confirm orientation and choose a replacement. Readable in any PDF viewer. Check that the marking on the component matches K772 and that a substitute shares the same package and electrical limits.
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.