Specification sheet in PDF format, 43.9 KB, for the 2SD2177A, the A-suffixed variant of the 2SD2177, with an additional _E tag in the name. Under JIS numbering, 2SD means an NPN bipolar transistor for low-frequency use. The file is indexed as a schematic but is probably a datasheet. Letter suffixes on JIS parts can indicate different ratings, so compare this sheet with the plain 2SD2177 version and check the marking on the original component before substituting one for the other.
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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