A 297 KB PDF describing the 2SC4251 transistor. The name contains just the part number, so the issuing manufacturer and revision must be read inside the document. Under JIS numbering, 2SC indicates an NPN transistor meant for high-frequency service. Typical uses at the bench include confirming pin order, checking breakdown voltage and maximum collector current, and reviewing hFE grading when hunting for an equivalent. Match the printed code, usually C4251, and the package outline before soldering in a substitute.
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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