Category Archives: 1977

In 1975, Commodore acquired it’s microprocessor subsidiary MOS Technology, who brought with them designs for a computer kit based on their 6502 microprocessor. Deciding not to focus on building calculators, Commodore president Jack Tramiel ordered the design of a machine around the kit at the urging of designer Chuck Peddle. Commodore’s first full featured computer, the PET (Personal Electronic Transactor), was born.

The first model was the 2001, introduced in September 1977. It included either 4k or 8k of RAM. It was essentially the computer kit based around the MOS display chip, which supported a built in monochrome monitor. It also had a Datassette in the front of the case for storage. After being backordered for months, the 4k model was discontinued to ease the burden. It was very successful but many complained about the small keyboard, which had space sacrficed for the other parts of the machine which was all built into one unit. Later models made the Datassette external and included larger keyboards. Unfortunately the line was beaten by competitors such as the Tandy TRS-80 and Apple II, which offered color graphics.

The total cost of producing the PET, including shipping, was 1/70 of it’s price. The company also noticed users were buying the later model’s cheaper 4k versions and upgrading the RAM, so they punched out the extra slots in motherboards.

The TRS-80 was a series of models sold by Tandy through Radio Shack stores in the 70s and 80s. Announced in August of 1977, it was intended to compete with the Commodore PET and the Apple II. The original production was limited to 3,000 machines, just in case the market didn’t do well. Exceeding expectations, they sold 10,000 the first month. By the time it was discontinued in January 1981, 250,000 units of the Model I had been sold.

TRS-80 machines were all powered by the Zilog Z-80 microprocessor. They supported up to four floppy drives, and hard disks were available (though expensive) for them as well. While it’s true that the original machine, the Model 1, was a little flaky and probably deserved the nickname “Trash-80” at times, the rest of the product line was pretty solid. And even the Model 1 could be “fixed”. The basic system sold with 4k of RAM, which was increased to 16k in later systems but was exapandable to 48k. Thier most familiar feature was the cassette drive on which data was stored. It orginally shipped with a black on white display, but later models were produced with color. It also included two versions of BASIC. The Model II came later and was aimed at business, with an 8″ floppy and 64k of memory.

Priced at $599, the TRS-80 was the most expensive single item Radio Shack had ever sold. They had originally intended to use it in the chain’s stores if it didn’t do well.

Mashable has a fascinating look at a 1981 Radio Shack catalog, naturally packed with all things TRS-80; http://mashable.com/2015/02/06/radio-shack-catalog-1981/

After Wozniak had completed design on the Apple-1, he already had in mind enhancements that would make his computer faster and more functional. He wanted to make it display in color. He worked to combine the terminal and memory functions of the Apple-1 by moving the display into main memory, allowing instant screen changes. None of these modifications were made specifically to make it a better product, or to make it more attractive for a customer to purchase.

Built in 1977, the Apple II was based on Wozniak’s Apple I design, but with several additions. The first was the design of a plastic case–a rarity at the time–which was painted beige. The second was the ability to display color graphics–a holy grail in the industry. The Apple II also included a larger ROM, more expandable RAM (4K to start), and 8 expansion slots. It had integer BASIC hard-coded on the ROM for easier programming, and included two game paddles and a demo cassette for $1,298. In early 1978 Apple also released a disk drive for the machine, one of the most inexpensive available. The Apple II remained on the Apple product list until 1980. It was also repackaged in a black case and sold to educational markets by Bell & Howell.