This 93.5 KB PDF is named 2sb1198k, a JIS transistor number with a K suffix that is part of the stated designation; it is catalogued as a schematic but likely a datasheet. The 2SB prefix marks a PNP low-frequency transistor. Suffix letters often distinguish package or variant, so make sure the code on the board corresponds to the K version before applying its data. Inside you should find pinout, outline, ratings and characteristic curves, viewable in any PDF reader.
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.