A 320 KB PDF dealing with the 2SC3123, an NPN bipolar transistor by its Japanese JIS 2SC code. Filed among schematics, the name holds nothing but the part number, pointing to a manufacturer data sheet. On the board the part typically shows C3123. Inside expect maximum ratings, electrical characteristics and a package drawing. Use them to verify the pinout prior to diode-mode junction checks, confirm the footprint, and make sure a proposed substitute matches or exceeds the voltage, current and dissipation limits.
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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