Reference PDF for the 2SB1438 transistor, about 44 KB, carrying an _E suffix that most likely marks the English version, and listed among schematics although it reads as a datasheet. In Japanese JIS numbering, 2SB stands for a PNP low-frequency transistor. The name supplies no other details. Repair technicians use it to read pin order, package dimensions and maximum ratings, helping to confirm a failure and pick a replacement that fits the board and handles the circuit voltage.
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.