At 33.6 KB, this PDF named 1N746 is a short component datasheet for the original non-suffixed part of the 1N746 zener family, indexed under schematics. It should state the nominal zener voltage, test current, impedance and maximum dissipation, with package details. Older equipment often uses the plain-numbered version, and the sheet helps confirm specification and decide whether a newer suffixed type is an acceptable replacement. Compare tolerance and wattage carefully, since the suffix versions can differ in voltage tolerance.
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.
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