The Kenbak-1 is considered by many the world's first personal computer, as it was a complete stand-alone system with processor, memory, and I/O. It was provided in kit form, and sold for $750 from 1971 to 1974.
The system had no microprocessor, its design predates the commercial release of the microprocessor. Its processor is built from general purpose TTL logic. Its instruction cycle is about 1 uS, giving it a processor speed of about 1MHz.
The system had 256 bytes of shift register memory, a bank of switches and lights.
Historical Significance

The Kenbak-1 is mainly a historical curiosity. Fewer than 100 units were sold during its commercial life, and it had little or no influence on later designs.
Its competitor for the title of "first personal computer", the [wiki]Datapoint 2200[/wiki], became commercially available at about the same time as the Kenbak-1. By contrast, the Datapoint 2200 sold many units, and was a seminal influence in the design of 8 bit microprocessors as the Intel 8008 was developed, in part, to meet a specification issued for a processor to be used in the Datapoint system.

The unique position of the Kenbak-1 in history has spawned a modern kit based on the original design, the Kenbak-1 Series 2. The design of the system still suits it admirably to the purpose of the original kit, an educational computer system. The use of logic to build up the processor makes the internals of the system accessible in a way that is impossible with a microprocessor.
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