Datasheet in PDF form, 474 KB, for the 2SC5086 NPN bipolar transistor, indexed in the schematic category. The name lists no manufacturer, package or revision. A technician would use it to identify the emitter, base and collector leads, review voltage, current and dissipation limits and compare gain groups when replacing a failed part. An FT-suffixed variant also appears in the index, so confirm which version is installed by reading the body marking before choosing the matching document.
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.