Series datasheet spanning the 1N5391 to 1N5399 diodes, a 42.7 KB PDF catalogued as a schematic. The range in the name indicates one document listing every voltage grade of the family in a shared table, which is handy when the marking on a damaged part is only partly legible. Technicians use it to compare grades, select a higher-voltage substitute and confirm package dimensions. Any PDF reader opens it. Match polarity to the cathode band and ensure the substitute meets all original ratings.
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 @cyberlanelectonik. 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.