Datasheet PDF for the 2SC5376F, a variant of the 2SC5376 NPN transistor; the trailing F usually indicates a different package or grade, though the name does not explain it. The 145 KB file is listed as a schematic but should contain component specifications such as voltage and current limits, characteristic curves and package dimensions. Compare it with the plain 2SC5376 sheet before substituting one for the other, since pinout or case can differ. Check the marking on the board part to be sure.
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.