MITS Advert - August 1975

If there's one microcomputer that can claim to be the grandaddy of the entire industry then it's this - the Altair 8800, from Micro Instrumentation and Telemetry Systems, better known as MITS.

Developed during 1974 and launched in January 1975, it was built around Intel's 8080 CPU. It was available in kit form, as well as pre-assembled, and was programmed via switches and lights.

It was built around the mainframe concept - literally a metal chassis/frame with slots for additional plug-in boards. This was originally known as the Altair bus, but became known as Standard-100, or S-100 bus, on account of its two-sided 50-pin socket format.

IMSAI picked up on this and released its IMSAI 8080, based on the same Altair bus, and in doing so established S-100 as a standard. Before long, there were hundreds of companies building S-100 cards, and many more microcomputer companies producing computers compatible with the S-100 bus.

A text-heavy advert, primarily for the Altair, now branded as the 8800a, but also mentioning the 8800b version and the new 680b, based on the Motorola 6800. Prices, as featured in the December 1976 edition of Popular Electronics, ranged from £395 for the "680b turn-key model kit" up to $10,000 for a multi-disk system. That's a not-insignificant £70,700 in 2024 money

When the Altair 8800 was released, a young Paul Allen and Bill Gates speculatively asked MITS if it needed a BASIC interpreter for its new computer. MITS said yes and so Allen and Gates ended up writing a version of BASIC on a DEC PDP-10, which they completed within a month.

Their port of the language was a success - it worked - and so they established a company as a result. That company was Micro-Soft, or Microsoft as it is now known.

The early computer industry was very liberal in its interpretation of copyright and such. Microsoft's BASIC became the de-facto standard language for the Altair, as well as most of the other micros of the era. However, whilst MITS was selling about 1,000 Altair micros a month, Micro-Soft's sales were in the low hundreds^[1].

This came to a head whe Gates wrote his famous open letter^[2] in 1976 to the Homebrew Computer Club complaining about how Micro-Soft's Altair BASIC was being freely copied.

MITS owned a converted camper van which was used to tour the U.S. and demonstrate its products. It had visited the Homebrew Computer Club, but the paper tape that was used to store a pre-release version of Micro-Soft's Altair BASIC disappeared for a while, and at the following week's meeting 50 copies of it appeared in a cardboard box^[3].

The bare-bones Altair retailed for $439, or about £3,760 in 2024, whereas the BASIC System - which included BASIC and an interface of choice, either serial, TTY (teletype) or audio cassette - retailed for $995, or about £8,780 now.