Datasheet in PDF for the KSC3503, an NPN transistor; the file name gives only the part number, so ratings must come from the document. This type is often found in video output, CRT driver and other high-voltage small-signal stages, and it pairs with a PNP complement in some designs. The sheet lets a technician confirm pinout, collector-emitter voltage, gain and power dissipation before choosing a replacement. Check the case marking carefully, since the 2SC prefix is frequently dropped on the body. Opens with any PDF reader.
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.