A 305 KB PDF for the 2SC4246 transistor. The name states nothing apart from the part number, so the manufacturer and revision have to be read inside the document. In Japanese JIS designations, 2SC stands for an NPN transistor of the high-frequency class. Repair technicians use such sheets to identify leads, confirm voltage, current and power limits and review hFE ranks before choosing a substitute. Verify the C4246 marking and the package on the actual component so the replacement fits and performs correctly.
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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The standard format for schematics, block diagrams, power-sequence charts and service manuals.