Radio Shack personal computer model TRS 80 III, c1981.
Radio Shack personal computer model TRS 80 III, c. 1981. Introduced in August 1977 by the retail electronics chain Radio Shack, the TRS 80 was the first complete, pre-assembled small computer system on the market. The Level 1 basic computer came with 4k RAM, a monitor, a cassette and all the cables and adaptors needed and sold for $599.95. The Model III improved on its design by integrating the monitor and keyboard in one unit and having a faster cassette interface. Both were powered by the Zilog Z-80 microprocessor and had Microsoft Basic built in.