Covering the 2SC4523, this 90.3 KB PDF is a semiconductor data sheet rather than a board schematic, despite its catalogue category. The 2SC prefix follows the Japanese JIS convention for NPN bipolar transistors. No manufacturer or package is stated in the name. Use the sheet to read pinout, maximum ratings and gain, then confirm the original component marking matches before swapping it, since similar numbers from different makers may use different packages.
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.
Any PDF readerSumatraPDFFirefox / ChromeFlexBV (links PDF to boardview)