Reference PDF for the 2SD1882, a JIS-registered Japanese semiconductor, filed in the index under schematics although it is most likely a component datasheet. In the JIS naming system the 2SD prefix marks an NPN bipolar transistor meant for low-frequency work such as audio output, switching and power regulation stages. The 89.6 KB document helps confirm pinout, voltage and current limits and gain before picking a substitute. Check the body marking, since Japanese parts often omit 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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The standard format for schematics, block diagrams, power-sequence charts and service manuals.