Here the 2SB819 is covered in a 51.8 KB PDF, with an _E ending in the name that is not explained and should not be read as a specific grade without checking the document. A 2SB number under JIS marks a low-frequency PNP transistor. Typical bench use is confirming which leg is collector, how the package is drawn and what voltage, current and dissipation limits apply, so you can test the original part with a meter or pick a safe substitute.
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.
Any PDF readerSumatraPDFFirefox / ChromeFlexBV (links PDF to boardview)