The largest of this group at 334 KB, this PDF is named only 2SC4117 and, while labelled a schematic, should be the datasheet for that NPN bipolar transistor under Japanese JIS numbering. On boards the part usually shows the shortened code C4117. Technicians open it in any PDF reader for pin order, package drawing, maximum ratings and performance graphs when testing a suspect device or approving a substitute. No manufacturer or document version appears in the name, so match the marking and case of the installed part first.
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.