Datasheet PDF, 60 KB, for the 2SD1650, with the name given in lowercase and filed under schematics. The 2SD prefix in the Japanese JIS system means an NPN bipolar transistor for low-frequency or power work. Contents are likely limited to essential ratings, electrical characteristics and the package outline. That covers the usual repair needs: pin identification, out-of-circuit testing with a diode-mode meter and checking that a substitute meets or exceeds the original limits. Any PDF reader opens it.
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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