Datasheet for the TIP41C NPN and TIP42C PNP complementary power transistors, a 195 KB PDF. The C suffix denotes the highest voltage grade in the series, and the sheet should list collector current, dissipation, gain, safe operating area and TO-220 pinout. Technicians use it for amplifier output stages, motor drivers and regulator pass elements, checking junctions with a meter, confirming heatsink tab connection and choosing equivalent parts. Open it in any PDF viewer and check the exact suffix printed on the part before substituting a lower grade.
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.