When Radio Shack introduced the TRS-80 Color Computer in 1980, it was a remarkably simple machine. A keyboard, a television, a cassette recorder and a cartridge slot were enough to get started.

For many owners, they weren't enough for very long.

Almost immediately, Color Computer users began looking for ways to make their machines do more. More memory. Better keyboards. Disk drives. Printers. Modems. Better displays. More cartridge slots. Speech. Music. Hard drives. Laboratory interfaces. Home automation. Robotics.

If the Color Computer couldn't do something, chances were good that somebody would figure out how to make it do it.

Radio Shack produced an extensive line of peripherals of its own, but an enormous third-party industry grew alongside it. Some products became commonplace. Others were produced in small quantities. Some are known today only through advertisements, magazine articles and surviving documentation.

And a few leave us asking a rather interesting question:

Did this thing actually get made?

CoCo owners didn't always wait for someone else to manufacture what they wanted.

Magazines such as The Rainbow and HOT CoCo, along with books, newsletters and user groups, published hardware projects ranging from simple cables and switches to memory expansions, video interfaces, disk controllers, EPROM programmers, robotics and complete peripheral interfaces.

With a soldering iron, a handful of components and a willingness to void the warranty, the Color Computer could become almost anything.

The Color Computer aftermarket became large enough that no single page can reasonably tell the entire story. The museum is therefore organized into the major categories below.

These sections will document both Radio Shack and third-party hardware, surviving examples, contemporary advertisements and documentation, and the people and companies responsible for creating it.

4K became 16K. Then 32K. Then 64K. The CoCo 3 went from 128K to 512K, then to one, two and eight megabytes.

And once owners started replacing memory, even the processor wasn't necessarily safe once the HD63C09 was uncovered as major upgrade.

The CoCo could make sound. Third-party developers decided it should make considerably more of it.

Speech synthesizers, music systems, multi-voice sound hardware, MIDI and even speech-recognition systems expanded the machine's audio capabilities.

Home automation isn't nearly as new as today's advertisements might suggest.

Relays, sensors, A/D and D/A converters, data-acquisition hardware, robotics and laboratory interfaces allowed the CoCo to interact directly with the physical world.

Buying hardware was only half of the Color Computer expansion story.

The other half involved a soldering iron.

The Rainbow, HOT CoCo, books, newsletters and user groups published an enormous number of projects that Color Computer owners could build themselves.

Some were simple cables and adapters. Others required circuit boards, ICs, power supplies and considerably more confidence.

Tony DiStefano's hardware articles alone covered printer interfaces, video circuits, sound generators, ROM switching, disk hardware, A/D and D/A conversion, relay systems, EPROM hardware and much more.

That tradition didn't disappear with the magazines. Modern Color Computer enthusiasts continue designing new hardware, publishing schematics, laying out circuit boards and sharing complete projects through open-source repositories.