An 84.6 KB PDF for the 2SC3071, filed as a schematic. The name supplies nothing beyond the part number, so this is probably a compact datasheet. A 2SC code in the JIS system designates an NPN bipolar transistor of the high-frequency type. A repair technician would use it to look up pin order, absolute maximum ratings and hFE classes. These help when testing a suspect part out of circuit or picking a substitute. Confirm the body marking matches before relying on the data.
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.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.