A larger 225 KB PDF for the 2SC3710A, an NPN transistor under the Japanese JIS designation, indexed as a schematic. The A suffix marks a variant of the 2SC3710 base number; its exact differences are not stated in the name, so compare the datasheet values with the part you have. Expect ratings tables, characteristic graphs and the package outline. Such a reference is used to identify pinout, assess whether the device was driven past its limits and choose a substitute with matching polarity, package and ratings.
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.