PDF of 41.0 KB for the 2SC3904 transistor, with an _E suffix in the name whose meaning is not stated, possibly an edition or language marker. The 2SC prefix is the JIS designation for NPN bipolar parts, so the content should be the component datasheet despite the schematic label. Look here for pin order, maximum voltage and current, gain ranges and package outline when testing or replacing the part. Verify the marking on the PCB matches before trusting pinout or 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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