Datasheet PDF for the 2SB1274, 34.4 KB in size and likely a concise sheet. The name offers only the part number. JIS nomenclature assigns the 2SB prefix to PNP bipolar transistors for low-frequency applications such as audio output and power switching. Expect pin assignment, breakdown voltages, collector current and power ratings. Repairers use it to interpret diode-mode readings in circuit and to evaluate cross-reference parts. Confirm that the package style and lead order match the board footprint and the original component marking.
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.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.