PDF document of 196 KB identified only by the part number 2SA2058. Under the Japanese JIS convention, 2SA parts are PNP bipolar transistors, so this is almost certainly a device datasheet rather than a circuit diagram. The file name states nothing else, such as maker, package or revision. A technician would read it for pin assignment, collector current and voltage limits and hFE grouping, then use those figures to verify a failed part or pick an equivalent with equal or higher ratings and the same footprint.
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.