At 192 KB this PDF is somewhat larger than its neighbours and covers the 2SC3142 transistor, an NPN bipolar part under JIS 2SC numbering. The extra size may mean more curves or packaging variants, but the name itself states only the part number. On a PCB the device often reads C3142. Technicians use it to look up the terminal layout, maximum collector-emitter voltage and collector current, and to evaluate equivalents when the exact part is hard to source. Verify the case marking before relying on the data.
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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