The 2SA1405 transistor is described in this 124 KB PDF, listed under the schematic type. Its JIS designation places it among PNP parts for high-frequency use. Beyond the part number, the name offers no detail on maker or variant. Technicians typically keep sheets like this for confirming the pinout of a component they are about to desolder, checking that measured circuit voltages are within its limits, and matching an available replacement with comparable ratings and package.
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.