Covering the 2SC3914, this 30.1 KB PDF belongs to the family of JIS-numbered NPN bipolar transistors identified by the 2SC prefix. The file name gives nothing beyond the part number, so treat the content as a datasheet rather than a circuit diagram. Use the pin diagram and ratings table to test junctions with a meter, confirm correct orientation, and evaluate whether a common substitute can handle the same voltage and current. Make sure the physical package on the board matches the one documented here.
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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