Datasheet for the SN7406N, a TTL hex inverter buffer/driver with open-collector high-voltage outputs in a plastic DIP package. The brief PDF, about 6 KB, most likely summarizes pinout and ratings. Since outputs need external pull-up resistors, a technician checking a stuck line should confirm the resistor and load as well as the chip itself. The document helps identify which pin is input or output for each of the six inverters. Verify the package suffix and marking against the board before replacing the IC.
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 @datasheet_technar_org. Enginerys does not host this file.
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