The 2sb1189 part number names this 42.5 KB PDF, which is placed in the schematic category but is most probably the transistor datasheet. JIS numbering gives the 2SB prefix to PNP low-frequency transistors, often found in power and driver stages. A technician uses the sheet to locate collector, base and emitter, check breakdown and current limits, and confirm hFE range when matching a substitute. Open it in a PDF reader and verify the package and marking on the actual device.
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.