Articles in the "Computers" Category

The Adcock & Johnson Model 3000

Before laptop computers, there were transportable computers. Transportable computers (sometimes known as “portables” or “luggables”) were smaller than ordinary microcomputers and could be quickly moved and set up at a new location. Unlike laptop computers (which had yet to be invented) transportable computers had no batteries and needed to be set up and plugged into an outlet before they could be used.

Starting around 1981, there was a trend toward transportable computers. The Osborne 1 (introduced in 1981) and Kaypro II (introduced in 1982) were notable examples of CP/M transportables. The Compaq Portable (introduced in 1983) was probably the most famous MS-DOS transportable and the product that created the Compaq brand.

The Adcock & Johnson Model 3000, introduced in the spring of 1982, was a third-party TRS-80 entry in the transportable market. The Model 3000 consisted of an actual TRS-80 Model III converted into a transportable computer, either as a factory conversion or as a kit.

The PMC MicroMate

The PMC MicroMate was a CP/M workstation introduced in April 1983 for the price of $1195.00, although that price was later reduced. It was sold by Personal Micro Computers, Inc, also known as PMC, already well known for the Model I compatible PMC-80 and PMC-81 computers. Although the computer lines were not really equivalent, the MicroMate replaced both the PMC-80 and PMC-81. The MicroMate was manufactured by PMC but also resold by TRIOS Micro Systems until late 1984 and was sometimes relabeled by them.'

The MicroMate, officially known as the PMC-101, featured a Z80A processor with 128K of memory and an integrated 5 1/4" floppy drive. The whole computer fit in a case the size of an external drive enclosure. In fact, the unit resembled the external drive units used on a TRS-80 Model I. The MicroMate had no keyboard or video display but was billed as a “Terminal Expander,” designed to be used with any terminal to run CP/M programs. In addition to CP/M 3.0, the MicroMate also came with the T/Maker integrated software package.

The LNW80

The LNW80, sometimes referred to as the LNW80 Model 1, was the first in a line of TRS-80 compatible computers sold by LNW Research Corporation (later known as LNW Computers). It was probably the most successful TRS-80 compatible sold in the United States. LNW Research had already created the LNW System Expansion, a replacement for the Radio Shack Expansion Interface, so the LNW80 was in many ways a natural next step.

When the LNW80 was introduced in 1980 it was originally sold as a $89.95 “semi-kit,” with instructions and bare printed circuit board. The semi-kit price was so low because all of the electronic parts required for the kit had to be purchased separately. Careful shopping could help reduce costs, but the complete inventory of parts cost hundreds of dollars.

Despite the name, the LNW80 “semi-kit” was not a project for beginners; according to Dennis B├íthory-Kitsz in his “80 Applications” column in 80 Micro there were 1,800 individual solder connections. For customers who wanted a complete computer, the LNW80 could also be purchased fully assembled, along with the LNW System Expansion, for $1450.00.

The Tandy 10

The Tandy 10 was the second computer introduced by Radio Shack, although it wasn’t part of the TRS-80 line. It was actually manufactured by Applied Digital Data Systems, also known as ADDS. ADDS (which still exists today as Boundless Technologies) was the largest independent supplier of video display terminals at the time. Unlike the TRS-80 computers, the Tandy 10 was branded using the Tandy name (Radio Shack’s parent company) rather than Radio Shack.

First offered in 1978, the Tandy 10 (catalog number 81-2110) was actually the ADDS System 50, a variant on the earlier System 70. Described as a workstation, the Tandy 10 was clearly targeted at businesses. It had a good set of features for a computer at that time:

The Lobo MAX-80

The Lobo MAX-80 was a TRS-80 compatible computer sold by Lobo Systems (originally known as Lobo Drives International). Introduced at the 1982 National Computer Conference (where one could be reserved for a $100.00 deposit), the MAX-80 offered an impressive array of features including:

  • a Z80B running at 5.07 MHz (making it one of the fastest microcomputers at the time)
  • 64K of memory standard, with sockets for an additional 64K
  • a double-density floppy disk controller with support for both 5 1/4" and 8" drives
  • a hard disk controller interface
  • video support through a standard RCA phono jack
  • a screen size of 64 by 16 or 80 by 24 with a partially redefinable character set
  • a TRS-80 style keyboard with CONTROL and ESCAPE keys, as well as F1 through F4
  • one parallel port
  • two serial ports
  • real time clock with battery backup

The Phoenix

One of the more intriguing TRS-80 clones was the Phoenix, first advertised by Progressive Electronics in the August 1983 issue of 80 Micro. Designed by Keith Helwig, one of the proprietors of Progressive Electronics, the Phoenix was manufactured and sold in Lancaster, Ohio.

The Phoenix was offered in two configurations. The first was the “Basic kit” which cost $599.00 and included:

The PMC-80

The PMC-80 was the North American version of a TRS-80 Model I clone that was created by EACA International Limited, a Hong Kong manufacturing company. Their Model I compatible computer was sold around the world by different distributors using different names. In Australia and New Zealand, it was the System 80. In Europe, it was the Video Genie. In the United States and Canada, it was the PMC-80, distributed by Personal Micro Computers.'

The TRS-80 Model III

Radio Shack introduced the eventual replacement to the Model I, the Model III, in 1980 (the Model II, introduced in 1979, was part of a separate line of business computers). Unlike the Model I, the Model III was an all-in-one design; the monitor, keyboard, and disk drives were all in the same unit. This cut down on radio interference and helped with school sales (which were concerned with students walking away with computer components in their bags). Like the Model I, the Model III used a Z-80, but running at 2.0 MHz this time. The Model III was largely, but not completely, software and hardware compatible with the Model I. It featured a more powerful 14K Level II BASIC ROM, lowercase support, and had a numeric keypad built right in. It had sockets to support up to 48K RAM internally, two internal drive bays, and with an optional floppy disk controller, operated in double-density by default.