Datasheet for the 1N5817 Schottky rectifier, a 1 A, 20 V part, saved as a 74.5 KB PDF and filed under schematics. The name lists only the part number, so manufacturer and revision are unknown. Expect maximum ratings, forward voltage curves and the case outline. Low forward drop makes this diode common in battery and low-voltage supply paths, and the sheet helps confirm a correct swap. Open it in a standard PDF viewer and check that the replacement voltage grade is at least equal.
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.