The 2SD1511 NPN transistor is the subject of this 56.9 KB PDF, filed under schematics in the index. JIS numbering assigns 2SD to low-frequency NPN bipolar parts. The extra E after the number is not defined by the name, and no package or maker is stated. The document should provide voltage, current and power limits along with an outline drawing. Use it to confirm the pinout, diagnose a failed stage and pick a replacement with equal or better ratings.
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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