ZIP archive of 6.17 MB for Apple logic board 820-00239. The name carries only the board number, and the size suggests a full schematic set or a schematic combined with a boardview. Such files help a technician trace rails from the power input through to the CPU and GPU, locate components and find test points for measurement. Confirm that the 820 number on the PCB matches before use, because related Apple models often have separate boards with different circuit details.
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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