BINAC, the Binary Automatic Computer, was an early electronic computer designed for Northrop Aircraft Company by J. Presper Eckert and John Mauchly in 1949.

The BINAC was a bit-serial binary computer with two independent CPUs, each with its own 512-word acoustic mercury delay line memory. The CPUs continously compared results to check for errors caused by hardware failures. The 512-word acoustic mercury delay line memories were divided into 16 channels each holding 32 words (31-bit) with an additional 11-bit space between words to allow for circuit delays in switching. The clock rate was 4.25 MHz which yielded a word time of about 10 microseconds.

New programs or data had to be entered manually in octal using an eight-key keypad.

External link

• Unisys History Newsletter Volume 5, Number 1