PDF reference for the 2SA1574 transistor, 47.9 KB in size. Apart from the part number, the name says nothing about package, maker or revision. By the Japanese JIS convention, 2SA parts are PNP bipolar transistors intended for high-frequency use. The sheet should give absolute maximum ratings, electrical characteristics and a mechanical drawing with pin numbers. It helps when tracing a faulty stage or sourcing a replacement with equal or better specifications. Confirm the original marking and footprint before swapping parts.
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.