At 228 KB, this PDF for the 2SA1771 is among the larger sheets in the set, indexed as a schematic though it bears a JIS transistor code. A 2SA number designates a PNP bipolar transistor, and the name adds no maker or revision details. A technician uses such a datasheet to read collector-emitter and collector-base voltage limits, current and dissipation figures, and the pin arrangement, which matter when swapping a failed part or cross-referencing an equivalent.
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.