About 90 KB in size, this PDF carries only the 2SK2091 part number and is likely the datasheet for that N-channel field-effect transistor, despite being filed as a schematic. The 2SK prefix denotes an N-channel FET in Japanese JIS numbering, and the maker is not given. Consult it for voltage, current and on-resistance figures plus the package pinout. Compare the original part marking before trusting the values or fitting an equivalent 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.
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