Radio Shack TRS-80 Model III

The Model III is basically an upgrade of the Model I, which was released three years earlier. It has the same CPU, but it is faster, has more memory, and the floppy drives hold twice as much data, although the Model I could be upgraded to some of these features.

But the major reason for developing the Model III was because the FCC had just instituted new regulations about RF emissions generated by computers and other electronic devices. The Model I was completely unshielded and was unable to pass the emission restrictions.