Covering the 2SC2500, this PDF of about 180 KB is indexed as a schematic but by its name is a semiconductor datasheet. The 2SC prefix follows the Japanese JIS standard for NPN transistors. Expect pin assignments, a package outline and electrical characteristics in a file like this. Use it to confirm that a proposed substitute meets or exceeds the original ratings. Also check the base, collector and emitter order, which can differ between nominally equivalent parts from different makers.
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.