Owning a piece of computer history can be expensive and not much fun. You can buy a vintage MITS Altair 8800, one of the world’s first successful desktop computers, on eBay, but a good one will cost you over US$4,000. That’s why computer enthusiast Mike Douglas developed the Altair 8800 Clone. It’s a modern, inexpensive, functional reproduction of the historic Altair 8800 computer that uses 21st century technology to recreate a bit of computer history for hobbyists and educators.

When the MITS Altair 8800 hit the market in 1975, it was as if NASA started giving away Apollo space capsules. In those days, computers were still things that even people who worked with computers had trouble getting access to. They were large, expensive and still rare enough that you had to book time on them for even the simplest job. The MITS company of Albuquerque, New Mexico used the newly-developed Intel 8080 processor to change all that when it used the microchip as the basis for the Altair 8800, a computer that could sit on a tabletop and sold for only $621 assembled.

The computer featured on the cover of the January 1975 issue of Popular Electronics wasn't the first hobby computer, but it was the first that came as a complete kit instead of list of parts or, also a first, fully assembled and tested. Exactly how many were sold isn't known, but it's estimated over 2,000 were delivered into the hands of consumers and the Altair 8800’s computer bus became the defacto industry standard.

Using modern technology leaves the Altair 8800 with what is a virtually empty case

Today, all this is surprising when a computer can be plugged in and connected to the internet in a matter of minutes of unpacking. To modern eyes, the Altair 8800 looks incomprehensible. There’s no keyboard, no monitor and the first ones didn’t even have any ports. It was just a blue and white box measuring 7 x 17 x 17.5 in (17.7 x 43.1 x 44.4 cm) with rows of switches and LED lights on the front panel marked with cryptic labels such as “HLTA” and “WO.” It ran on undiluted machine language and programming it was a long, tedious process of flipping switches to input binary code. It was also prehistoric in performance with 64 K of RAM and a CPU running at 2 MHz. Then there was the fact that assembling the kit was a long, difficult job.

Despite all this, MITS couldn’t keep up with demand and some buyers camped in the company’s car park waiting for their machines. After they got their machines assembled, the enthusiasts would then rack their brains trying to figure out what to do with the things. Meanwhile, a company called Traf-O-Data offered to write a new version of BASIC as the operating system for the Altair 8800. The partners behind Traf-O-Data went on to start an obscure software company called Microsoft.

The front panel circuit board

The Altair 8800 Clone was started by Mike Douglas in 2012 when he discovered how much it would cost to buy a vintage Altair 8800. Even reproduction kits were expensive and hard to obtain, so Douglas decided to use the original data sheets and schematics to design his own replica with modern technology to emulate the original Altair 8800. The result was the Clone, which looks and acts like the original, but the inside is made of 21st century components. What started as a hobby became a business because producing things like custom casings or nameplates is only feasible when done in commercial runs.

The Clone duplicates the look, feel, features, and performance of an Altair 8800 down to the limitations and quirks, and it will run software written for the Altair 8800. This has a strong educational and nostalgia factor because, for all its historic significance, the Altair 8800 had some real design problems. The only thing the Clone can’t do is play “The Fool on the Hill” over an AM radio as an early Altair 8800 was famously programmed to do. That’s because the modern parts don’t bleed radio emissions, so they can’t be manipulated to play songs on a receiver.

The most obvious difference between the Clone and the Altair 8800 is that the former is suspiciously light. The modern components are so small compared to the original that the the power supply, circuit boards and buses have been replaced with a whole lot of nothing. At first glance, it looks like an empty box with a few wires running between the front and back panels. The case itself is an original design to emulate the Altair 8800s, though simpler inside to keep down construction costs.

An unpainted Altair 8800 Clone case

The other difference between the Clone and the earliest Altair 8800s is that it has two external RS-232 serial ports as well as provisions for a printer and cassette interfaces if the user wishes to make modifications. Floppy drives for an Altair 8800 are harder to come by than the computer, so the Clone emulates these with virtual drives that allow users to “insert” a virtual disc using a PC. Once this is done, the Clone can emulate a floppy disc boot up without being reconnected to the PC.

Like the original, the Altair 8800 Clone is available fully assembled or in kit form. In addition, there are online tutorial videos and documents for using the hardware and how to program it. According to the company, the kit takes only a few hours to build, but recommends this only for those who have experience soldering circuit boards.

The Altair 8800 Clone sells for $621, which is the same price as an original assembled Altair 8800 in 1975. Oddly, the price for the kit version is the same because it turned out to actually be cheaper to offer the Clone assembled.

The video below is a technical introduction to the Altair 8800 Clone control panel.

Source: Altair 8800 Clone via classiccomputing.com