PDF document, 142 KB, named for the 2SD1828, an NPN bipolar transistor going by the JIS 2SD prefix for low-frequency types. Although it is indexed as a schematic, expect datasheet content: electrical characteristics, a package drawing and rating tables. These details help when you diode-test a suspect transistor in circuit or select an equivalent part. Pin order differs between case styles, so verify it against the footprint on the PCB before soldering.
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.
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