Datasheet for the 4N38 optocoupler, marked as revision 2 in the name and supplied as a 294 KB PDF filed among schematics. The 4N38 belongs to the classic 4N family of phototransistor-output optoisolators, used for isolated signal transfer and power supply feedback. Expect pinout, current transfer ratio, isolation voltage and switching times. Technicians use it to check a suspect isolator with a meter and LED test, and to confirm pin compatibility before swapping in an equivalent from another manufacturer.
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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