A 40.8 KB PDF for the 2SA1290 transistor, catalogued under schematics. The filename states only the part number; the 2SA prefix designates a PNP bipolar device in the JIS system, pointing to a component datasheet. It should give lead identification, case outline and electrical limits. Open it in any PDF viewer when you need to check pin order before fitting a new part, or to compare collector-emitter voltage and current ratings against a proposed substitute so the repaired stage is not overstressed.
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.