A 109 KB PDF for the 2SK1439, filed with schematics but most likely the manufacturer's data sheet for this transistor. The JIS 2SK prefix denotes an N-channel FET. No package, maker or revision appears in the name. The sheet supports fault finding by giving pin order, absolute maximum ratings and switching characteristics, and it helps when choosing a substitute with equal or better limits. Confirm the device code printed on the part before replacing it.
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.
Any PDF readerSumatraPDFFirefox / ChromeFlexBV (links PDF to boardview)