A 44.1 KB PDF for the base 2SD2177 transistor, the name also carrying an _E suffix. The 2SD prefix in the Japanese JIS scheme marks an NPN bipolar device for low-frequency applications, so this is likely datasheet content filed under schematics. Manufacturer and package are not given. An A-suffixed 2SD2177A sheet exists separately, so verify which version is actually fitted. Use the document for pinout, absolute maximum ratings and gain figures when diagnosing or replacing the part.
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.