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Up for sale is an extremely rare piece of microcomputing history: a 1975 GNAT Computers ALU / Logic Processing Board for the S-100 bus (Altair 8800, IMSAI 8080).• Manufacturer: GNAT Computers (San Diego, CA)
• Markings: Top-right PCB silk-screen reads "(C) GNAT COMPUTERS 75" along with board number 3005.
• Key Components: Features two Texas Instruments SN74LS181N High-Speed Arithmetic Logic Unit (ALU) / Function Generator ICs, an AM25LS163 PC counter, and extensive TTL support logic—mostly featuring 1975 date codes.
• Interface: Standard S-100 100-pin gold edge connector. Includes onboard card-ejector handles.
• Condition: Clean, intact vintage condition with original solder joints and traces. Features period label marking on front ("@ ROM IF"). Sold UNTESTED / AS-IS for historical preservation, restoration, or vintage computer display.Item will be packed securely in anti-static ESD shielding for delivery.
