A schematic diagram. Shared as “KV-21V5_V6.pdf” — a .pdf file, 3.41 MB.
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 @pepeelectronica. 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.
Any PDF readerSumatraPDFFirefox / ChromeFlexBV (links PDF to boardview)