Circuit diagram for the Samsung SGH-X830 handset, in a 630 KB PDF. SGH is Samsung's prefix for its older GSM phones. The name gives no board revision. Technicians use such schematics to diagnose charging, power-on, audio, keypad and display faults by following the relevant lines and checking components along them. Use any PDF viewer to read it, and compare reference designators with the actual board, since part placement can differ between hardware revisions.
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 @mobileshematic. Enginerys does not host this file.
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The standard format for schematics, block diagrams, power-sequence charts and service manuals.
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