A 166 KB PDF covering the 2SK1961 transistor. The 2SK series in the JIS system denotes N-channel FETs, so this schematic-categorised file should be read as a component datasheet. It helps with locating gate, drain and source for in-circuit testing, checking drain-source voltage and current capability, and comparing on-resistance when cross-referencing. Since the file name mentions no manufacturer, package or revision, match the marking and package on the board before relying on the data.
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.