Processor Technology Corporation, a computer hardware manufacturer established in 1975, designed the SOL-20 in response to a request from Popular Electronics magazine. The magazine wanted a feature article on an intelligent computer terminal and Technical Editor Les Solomon asked Processor Technology to design one. It was featured on the July 1976 cover and became the SOL-20 Personal Computer. The first units were shipped in December 1976 and the SOL-20 went on to become a very successful product. However, the company failed to develop next generation products and ceased operations in May 1979.
Design work on the SOL-20 began between April and July 1975. The system utilized the Intel 8080 8-bit microprocessor chip, running at 2 MHz. A major difference between the SOL-20 and most other machines of the era was its built-in video driver, which allowed it to be attached to a composite monitor for display. The SOL-20 consisted of a main motherboard (PCB) mounted at the bottom of the case and a five slot S-100 bus card cage. The case, which was painted 'IBM blue', also included a power supply, fan, and keyboard. The sides of the SOL-20 case were made of solid oiled walnut originally salvaged from a gun stock manufacturer.
Processor Technology manufactured approximately 10,000 SOL-20 personal computers between 1977 and 1979. It was available either fully assembled or as electronic kits. Processor Technology also sold software on cassette tape.
Source: Wikipedia, "Processor Technology", available under the CC-BY-SA License.