A 64.4 KB PDF for the 2SA1906, with a 1-2 suffix in the name that may indicate the first of two pages or parts; the exact meaning is not stated. It is filed as a schematic but is most likely datasheet material. A 2SA number in the JIS system denotes a PNP bipolar transistor. Use it for pinout, voltage and current ratings and package information, and look for the companion portion if details seem missing. Always match the marking on the removed component before ordering 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.