Datasheet for the 2SD2357 NPN transistor, 39.8 KB in PDF format and filed under schematics. The 2SD prefix follows JIS rules for low-frequency NPN bipolar parts, and the trailing E has no stated meaning in the name. The sheet likely lists maximum collector-emitter voltage, collector current, dissipation and the pin diagram. Check those values before swapping in a substitute. Always confirm the package type against the part fitted on the board.
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