For the 2SD2098 transistor, this 159 KB PDF is categorised as a schematic but follows the usual naming of a part datasheet. The JIS 2SD prefix stands for an NPN bipolar transistor for low-frequency use, typical in regulator, switching driver and amplifier stages. Use it to verify pin order before soldering, since the arrangement varies between packages, and to compare ratings with any proposed substitute. Confirm that the device on the board actually carries this code, as body markings often drop the 2S prefix.
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.
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