Top 10 Personal Computers of the Past

Personal computers were, 30 or 40 years ago, a revolution. For the first time a person could have a computer at home. And although they were not precisely powerful machines, they served to form an entire generation of hackers. That's why we propose a tour of the ten most famous home computers of all time.

Amstrad CPC

Founded in 1968 by Alan Sugar, “Amstrad” is a contraction of Alan Michael Sugar Trading. Amstrad began selling its own personal computers in 1984, trying to win a share of the market held by Commodore and Sinclair. The CPC 464 model of that year was based on an 8-bit microprocessor, the Zilog Z80. It ran at 3.7 MHz and had 64 Kbytes of RAM. Hard drives were too expensive at the time, so programs were stored on audio cassettes, thanks to a built-in tape drive in the computer's case.

It could be purchased with a color or green phosphor monitor, and was sold in the UK, France, Australia, Germany and Spain, where it was a sales success. Soon after, the company presented the CPC 664 model (with a 3-inch disk drive) and the CPC 6128 (with 128 Kbytes of RAM and a more professional keyboard). So great was the success of these computers that in 1986 Amstrad bought its biggest competitor: Sinclair Research. Amstrad continued manufacturing computers until the end of the 90s. Those later models ran Windows and used Intel microprocessors (80386).

Apple II

The company that today sells millions of iPod and iPhones began making Home Computers back in the 70s. The first model, the Apple I was little more than a puzzle to assemble, which only a handful of people could use. But the Apple II radically changed the company's future.

The first Apple II units went on sale on June 5, 1977. They were built around a 6502 microprocessor running at 1 MHz, and had 4 KB RAM, 12 KB ROM (with the BASIC programming language inside). Like other computers of the time, it used audio tapes to store data and programs.

The Apple II's video system only displayed 24 lines of 40 columns of uppercase text. The composite NTSC video output could be seen on a monitor, but if you bought an RF modulator you could use a regular TV as a monitor. The launch price of this computer was US$1,298 (with 4KB RAM) and US$2,638 (with 48KB RAM). Thousands of schools equipped their computer labs with these computers during the 80s.

Over time, many peripherals and more complete models appeared. For example, the 'Disk II' was an external 5¼-inch floppy disk drive, much more efficient and faster than cassettes. This disk interface, created by Steve Wozniak, is now considered a marvel of design. In 1986 the Macintosh line began to displace the Apple II. However, the company continued to sell and support its Apple II computers until 1993.

Atari 400 and Atari 800

Atari computers were among the best-selling during the 80s. The company was known for its game consoles, like the Atari 2600, but in 1979 it ventured into the Home Computers market with two almost mystical models: Atari 400 and Atari 800. The names of these computers were due to the amount of memory they originally incorporated: 4K of RAM in the 400 and 8K in the 800. However, RAM prices began to drop, and the machines were upgraded to 8K and 16K respectively.

The price of the Atari 400 was originally $549.95, and it had a 6502 micro running at 1.8MHz, with 8K of RAM (expandable to 48K). It could display 24 lines of text with 40 columns, and had two graphics modes: 320 x 192 pixels in monochrome, or 160 x 96 pixels with 128 colors. It had ports for four joysticks, cassette recorder and floppy disk drive. The keyboard was rubber membrane.

The Atari 800 model was available for $999.95, and differed from its 'little brother' in its 16K of RAM (also expandable to 48K) and its 'professional' keyboard, with plastic keys like those of a modern computer.

Atari continued to manufacture computers for several years, with models like the 600XL, 800XL, 1400XL and 1450XL. In 1983 Jack Tramiel (owner of Commodore) bought Atari's Home Computers division, and built the 65XE and 130XE models. In 1992 the company officially closed its line of home computers.

Commodore 64 / Amiga

Few computers will be as remembered as the Commodore 64 or Commodore Amiga. These machines were the best-selling of all time. The company was founded by Jack Tramiel in the 50s, and began repairing typewriters. In the early 70s it took control of MOS Technology, the company that manufactured the 6502 microprocessor, which it used in many of the computers it would later create.

This model had a 6510 micro at 0.985 MHz (PAL) or 1.023 MHz (NTSC), 16-color video, with a text mode of 25 lines of 40 columns. Characters were formed by 8x8 pixel blocks. The sound was very good, provided by an MOS Technology integrated circuit, the 6581/8580 SID. RAM was 64KB, but only 38KB were available for BASIC programs. It had an RS232C serial port, connection for floppy disk drives and cassette, two joystick ports and output for TV or monitor. It cost $595.

The Commodore Amiga was a more professional computer. The most famous model, the Amiga 500, began production in 1987. It used a 68000 processor at 7.16MHz, and had an impressive 512KB of RAM and another 512KB of ROM. Its graphics were very advanced for the time, and it had three video modes: 320x400 pixels with 32 colors, 640x400 with 16 colors, or 320x200 with 4096 colors simultaneously.

But the most important thing about this computer was its highly advanced operating system, Amiga OS, inspired by Apple Macintosh. It was the first personal computer to allow true multitasking. It had specialized chips for video and sound handling. It originally did not have a hard drive (only floppy), but later models allowed the connection of SCSI hard drives and CD-ROM. It cost (without monitor) $595.95.

IBM PCjr

IBM also wanted a slice of the Home Computers market. The IBM PC, born in 1981, was too expensive for most home users, so the engineers at Big Blue thought about how to reduce costs. The result was the IBM PCjr, a sort of cut-down IBM PC.

Announced in 1985, the PCjr came in two flavors: the 4860-004 model, with 64K of RAM and a base price of $669; and the 4860-067, with 128K of RAM and a 5.25-inch floppy disk (360K), for $1269. The PCjr claimed a high degree of compatibility with the IBM PC, which was already popular, and offered color graphics and sound comparable or superior to other home computers of the time. Its Intel 8088 microprocessor at 4.77MHz was faster than the competition.

However, it was not the success IBM had hoped for. The PCjr's price was not competitive, costing more than twice as much as a Commodore 64 or an 8-bit Atari. For that money, one could buy a computer with two tape drives, a printer, and plenty of software.

MSX

Actually, it is not a computer, but a specification that Microsoft tried to impose in 1983. In fact, it is said that MSX is the acronym for MicroSoft eXtended. The idea was actually quite good. At that time there were more than 50 personal computer manufacturers, each with its own operating system. When a software company created a game or application, it had to port it to several totally incompatible platforms.

MSX defined an 8-bit architecture that was supported by about thirty manufacturers, including Canon, Casio, Panasonic, Philips, Sony, Toshiba and Yamaha. It was very successful in Europe, Brazil, Chile, Argentina, Japan and Russia, but in the US it never caught on.

The features of these machines included a Z80 microprocessor, a programming language called MSX-Basic (from Microsoft), a disk operating system (MSX-DOS) compatible at the file level with MS-DOS from IBM PC, cassette interface, minimum RAM of 8 KB (many MSX computers had 32 KB or 64 KB, and some reached 512 KB). Video memory was 16KB and allowed text modes of 40×24 and 32×24 and a graphics mode of 256×192 pixels with 16 colors. The MSX standard was followed by MSX-2, MSX-2+ and MSX turbo R.

Oric-1

The Oric 1 was a home computer manufactured by Tangerine Computer Systems to compete with the Sinclair ZX Spectrum. It appeared in 1983, and thousands of units were sold worldwide, but like other Home Computers, it disappeared from the market in the early 90s.

With a price of 129 pounds, the Oric-1 had a 6502 micro at 1 MHz, 16KB of ROM (BASIC included) and RAM between 16 and 64KB. The keyboard, made of plastic blocks, had 57 keys. The video did not have its own memory and used the system RAM. It could display 28 lines of 40 columns of text in 8 colors or graphics of 240x200 pixels with 64 colors. The sound was quite good, thanks to an AY-3-8912 chip that provided 3 channels of 8 octaves of sound plus one of white noise (mono, with 16 volume levels through an internal speaker).

Sinclair ZX81 / Spectrum

Sir Clive Sinclair was the Steve Jobs of the 70s and 80s. During those years, he seemed capable of creating any product and turning it into a success. The Sinclair ZX81 (successor to the ZX80) sold by the millions, largely due to its cost of only $100.

It had a Z80 at 3.25MHz, 1 KB (yes, 1KB!) of RAM and 8 KB of ROM, and its keyboard was membrane. It connected to a TV that served as a monitor, and programs could be recorded on a cassette recorder. BASIC instructions were entered quickly, since each key, in addition to the corresponding letter, had a BASIC command written on it. The graphics were very poor, formed by black and white blocks, with a resolution of 64x48 pixels. In text mode it displayed 24 lines of 32 characters.

The machine that took Sinclair to the top was the ZX Spectrum. Launched in April 1982, at a price of $299, it had everything the ZX81 lacked. Its most relevant features included a Z80 at 3.5 MHz, with an 8-bit data bus and 16-bit address bus, 16K (or 48K) of RAM, 16K of ROM with a BASIC SINCLAIR interpreter. The rubber keyboard, without being a marvel, was much superior to that of the ZX81. But where it really surpassed its little brother was in graphics. Its video system was capable of displaying 256x192 pixels with 16 colors. Thousands of games were written for this computer.

There were many versions of the ZX Spectrum. The best-selling were the ZX Spectrum 128 (128KB of RAM) and the models manufactured by Amstrad, such as the ZX SPECTRUM 128 +3, which included a 3-inch disk drive in the same case.

TRS-80

The Tandy Radio Shack Z-80 microcomputer (TRS-80 for short) was a system produced by Tandy Corporation and distributed by Radio Shack stores in the late 70s and during the 80s.

It went on sale in 1977, at a price of $599. It was intended to compete with the Apple II, and that price included a monitor (black and white, 12 inches) and a cassette recorder. Legend has it that Radio Shack had doubts about the success of this product, so it only manufactured 3,000 units: if it failed, they would be used for administrative tasks at the chain's branches. But it was a success: they sold 10,000 in the first month and 55,000 in the first year. It ceased production in 1981, after selling more than 250,000 units.

It had a Z80 microprocessor at 1.77MHz, 4K or 16K of RAM, and had two versions of BASIC, one of them with support for high-precision calculations.

TI-99/4A

Manufactured by Texas Instruments starting in 1983, it was a very popular computer in the 80s. It was also the first to have a 16-bit CPU, the TMS9900 running at 3.3 MHz. Some design errors prevented it from taking full advantage of this processor (for example, poor memory management or peripheral connection).

It was possible to use a normal television as a screen, or a monitor specially created for it. It could store data on audio cassettes or on 5.25-inch floppy disks (84 KB on a single side). The keyboard was of high quality, and the sound allowed three simultaneous voices. Texas Instruments equipped this computer with a large number of peripherals, including 132-column printers, speech synthesizer, hard drives, light pens, joysticks, etc.

The BASIC, and especially the so-called Extended Basic (provided in a plug-in cartridge) was one of the best available at that time, allowing easy management of graphics, sounds and even sprites. In 1983 it cost $525.

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