Service manual for the Samsung Galaxy A5 (2017), model SM-A520F, with the W variant also named, stored as a 7.84 MB ZIP. Samsung manuals generally include specifications, disassembly procedures, block diagrams, schematics and component placement. A technician uses them to trace power and signal paths, check for shorted lines with a meter and locate test points before replacing ICs. Extract it and open the PDFs in any viewer, and confirm the exact model code on the device, since regional variants can differ in RF sections.
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 @esquematicosdecelulares. Enginerys does not host this file.
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Compressed archive that every operating system opens without extra software.