Mr. John Blankenbaker

He designed and invented the Kenbak-1, considered by the Computer History Museum and the American Computer Museum to be the world's first "personal computer". He founded. Kenbak Corporation in 1970, and was first sold in early 1971. Only 40 machines were ever built and sold. The system first sold for US$750. Only around 10 machines are now known to exist worldwide, with various collectors. In 1973, production of the Kenbak-1 stopped as Kenbak Corporation folded. Since the Kenbak-1 was invented before the first microprocessor, the machine didn't have a one-chip CPU but instead was based purely on discrete TTL chips. The 8-bit machine offered 256 bytes of memory (=1/4096 megabyte). The instruction cycle time was 1 microsecond (equivalent to an instruction clock speed of 1 MHz), but actual execution speed averaged below 1000 instructions per second due to architectural constraints such as slow access to serial memory. To use the machine, one had to program it with a series of buttons and switches, using pure machine code. Output consisted of a series of lights.