The only detail in this 183 KB PDF name is the part number 2SD2461, indicating the datasheet for that transistor. According to the JIS scheme, 2SD components are NPN bipolar transistors designed for low-frequency circuits. Although filed among schematics, the document is used to read pinout, package drawing and absolute maximum ratings. Technicians reference it when checking a suspected short across collector and emitter or selecting a replacement. Confirm the device code on the PCB matches before ordering parts.
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.