The name gives nothing beyond 1N3085, a number in the JEDEC 1N series reserved for semiconductor diodes, so this 86.0 KB PDF is best treated as a part datasheet despite its schematic label. It opens in any ordinary PDF viewer. A repair technician would consult it for reverse voltage, forward current and package data when checking a shorted or open diode with a meter, or when choosing an equivalent part. Confirm the exact marking and any suffix on the original component, because suffixes change 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.