A schematic diagram. Shared as “an4171_25_w_mono_btl_classd_audio_amplifier_demonstration_board.pdf” — a .pdf file, 792 KB.
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 @pdf_servicemanual. 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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