Datasheet PDF for the 2SK1612, just 36.4 KB, indexed under schematics. The 2SK code marks an N-channel field-effect transistor in the Japanese part-numbering system; no manufacturer, package or revision is mentioned in the name. Any PDF reader opens it. Check the pin assignment and outline before desoldering, then use the voltage, current and power dissipation ratings to confirm that a replacement candidate is at least as capable as the original device.
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)