PCB document for an R2 power amplifier listed at 1000 watts, as a 3.50 MB PDF. The larger size suggests detailed artwork, possibly with both layers or component markings. R2 style boards are popular DIY class AB amplifier designs, and this file helps identify part positions, follow the output stage wiring and check tracks for damage. Open it in a PDF reader; before building or repairing confirm the layout matches your board and that the supply voltage and output devices suit the rating.
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.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.