The first 'Tandy' computer was the Radio Shack (TRS - Tandy Radio Shack) TRS-80. Called just the TRS-80, it later became known as the "Model I" when the TRS-80 Model II was announced in the summer of 1979. The Model I was invented by Don French (A buyer for Tandy) & Steve Leininger (The head of the Homebrew Computer Association) and first announced on Wednesday, August 3, 1977, in Radio Shack Press Release 7741-A, at a press conference at the Warwick Hotel in New York City. Radio Shack said they anticipated deliveries to start in two weeks, but was quite unsure of the product, thinking that they might sell 600 to 1000 the first year. It was also the most expensive single item Radio Shack had ever carried to that date. They required a $100 deposit to place the computer on order. In actuality 10,000 units were sold in the first month! Radio Shack was swamped with orders, and delivery times quickly fell to months after order. By early November of 1977, Radio Shack was delivering 16K RAM units with 5 digit serial numbers that had been ordered in early September. At that time, there were separate serial number sequences for 4K and 16K machines. The Model I began with a $599 Level I System with 4K RAM, monitor, and cassette, with all cables and adapters ready to go (except that it took 3 plugs, so you probably needed to purchase a power strip). The Level 1 was soon replaced by a 16K Level II System. The Level II (first model) was updated to include a numeric keypad.
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