The Altair—a do-it-yourself computer kit based on the Intel 8080 microprocessor—was featured on the cover Popular Electronics in January 1975 with the promise that readers could build their own mini-computer for under $400. It was designed by Ed Roberts at MITS (Micro Instrumentation and Telemetry Systems)—a small Albuquerque, New Mexico-based company that started out producing electronics kits for the model rocketry hobby. In 1971, MITS had some success marketing kits to make calculators, but found the demand evaporate once Texas Instruments started selling assembled-calculators for half the price. MITS—struggling under a load of debt—staked its future on the Altair. Roberts anticipated that he would sell a few hundred Altair kits, but orders quickly overwhelmed the tiny manufacturer. Production delays doubled, and even tripled the original 60-90 day shipping window; in the first three months alone, MITS sold 5,000 Altair kits.
So what did $397 buy? In short, not much—a box of parts, circuit boards, power supply, a case, some questionable instructions, and a whole lot of work. Building an Altair was an advanced course in wiring logic and soldering, and hobbyists—regardless of skill—rarely got it right the first time. Once completed—customers had a computer only 256 bytes of memory, and no input or output devices.
As sold, the Altair was not particularly practical, but the computing hobbyists who purchased it relished it. User groups formed around the country, including—most famously—the Homebrew Computer Club, whose members included several future luminaries of the personal computer revolution. The Altair also played an essential role in the founding of Microsoft when Bill Gates and Paul Allen developed a BASIC language interpreter for it.