Reference sheet in PDF form, 141 KB, for the 2SD2198 transistor. The file is indexed as a schematic but is most likely a datasheet. JIS part numbers starting with 2SD denote NPN bipolar transistors for low-frequency applications, often found in power and driver stages. Nothing else, such as maker or package type, is stated in the name. Open it in any PDF viewer to confirm base, collector and emitter pin order and the absolute maximum ratings when testing a suspect device or choosing an equivalent.
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.