PDF data for the 2SC3781 NPN transistor, roughly 128 KB in size, filed as a schematic though it is most likely a component datasheet. The 2SC code comes from the JIS numbering convention used for Japanese semiconductors. No board, device or revision is named. A technician can read off the maximum collector-emitter voltage, collector current, power dissipation and terminal order, which matters when testing with a multimeter or sourcing a substitute. Match the marking on the failed part before ordering.
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.