The 2SB1602 transistor datasheet, a 207 KB PDF filed among schematics. JIS numbering assigns the 2SB prefix to PNP bipolar transistors meant for low-frequency circuits, and the name gives no other device details. A technician pulls up this document to confirm base, collector and emitter positions, check voltage and current limits, and review dissipation versus temperature when deciding whether a part failed from overload. Substitutes should match package, polarity and ratings, not just a similar part number.
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.