PDF datasheet covering the 2SD2251 NPN transistor, 95.7 KB in size and listed under the schematic category. The name contains nothing beyond the part number. Japanese JIS numbering assigns the 2SD prefix to NPN bipolar devices for low-frequency use, common in audio, regulator and switching stages. When hunting a substitute, match the maximum voltage, collector current, power dissipation, gain and package from this sheet, and confirm the base, collector and emitter order before installing anything.
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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