A 136 KB PDF for the 2SK2503 whose name ends with _1-5, a suffix not explained by the name and possibly marking pages or a document edition. The 2SK designation identifies an N-channel FET in JIS numbering. A copy without the suffix is also indexed at the same size. Technicians use this sheet to find the gate, drain and source leads, check the voltage and current ratings and confirm that any replacement transistor meets them before soldering it in.
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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The standard format for schematics, block diagrams, power-sequence charts and service manuals.