Listed among schematics, this 78.7 KB PDF covers the 1SS399, a number that follows the Japanese 1SS small-signal diode designation. Nothing in the name points to a device, brand or revision; the trailing underscore is just part of the filename. The content is most likely a datasheet with electrical characteristics, a package outline and a marking code. During board-level repair it helps you identify a failed diode and confirm the replacement has equal or better ratings. Opens in any PDF viewer.
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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