PDF datasheet for the 2SB1288, 41.4 KB, with an E suffix in the name that most likely marks an English-language edition. Nothing else is stated about package or manufacturer. According to JIS coding, 2SB denotes a PNP bipolar transistor of the low-frequency type, widely found in audio, regulator and switching stages. The sheet gives the pinout, maximum ratings and characteristics needed to test or replace the part. Check the device marking and package against the drawing before ordering an equivalent.
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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