Zenith Minisport

The Zenith MiniSport, introduced in 1989 by Zenith Electronics Corporation, was a small laptop based on a 80C88 CMOS CPU running at 4.77 MHz or 8 MHz, software selectable.

It had one megabyte of battery-backed RAM, optionally expandable to two, ran MS-DOS from ROM, had a 640x200 pixel resolution LCD and CGA and composite monochrome outputs. The MiniSport was one of the first actual small laptops, apart from a contemporary NEC model.

Features

Unique features:

*2" floppy disk drive (720 kB double-sided, double-density). The 2" media was very expensive, typically $80 for a box of 10 floppies. Like many other laptops, an external 3.5" floppy drive was available as an accessory.
*Built-in "FastLynx" transfer software that could install itself on any other DOS computer over a serial cable without the need for any pre-existing software on the remote system. It relied on the user typing in a DOS Mode command on the other computer, which transferred control of that computer's command line to the Zenith over the serial line. The software then copied itself across, and the user could then move files. This to some extent compensated for the fact that no other computer ever used the 2" floppy disks, thus rendering floppy transfers impractical.
*The ability to set aside some of its upper memory (typically the 384k area between 640k and 1MB) as a battery-backed RAM disk; this was unique in DOS-based laptops. The RAM disk appeared as C: in DOS and enabled the computer to run with no spinning disks, extending battery life and increasing reliability. Contents were preserved with the power off, though using a minuscule amount of current from the main battery.
*Later versions included an integral 20MB (Megabyte) hard disc. This was enough to run WordPerfect and associated programs, including spell-checkers and diagnostic programs.

Disadvantages

*The MiniSport, like most personal computers of its day, had a battery which maintained the BIOS NVRAM. When this battery failed the computer would not boot until the user edited the configurable BIOS parameters. The Minisport NVRAM battery was replaceable.
*The Minisport's 2" floppy disks were not popular and were/are much more expensive than 5.25 and 3.5 inch floppy disks.
*The Minisport's LCD display, while backlit, lacks contrast and does not have an adjustable viewing angle, making it necessary to tilt the whole laptop to obtain the best view.

Dimensions

The MiniSport is 12.5" wide x 9.8" deep x 1.29" tall (318 mm x 249 mm x 33 mm), (lid closed), 7.75" (197 mm) tall (lid open). It weighs 5.9 lb (2.7 kg), with battery.

External links

* [http://www.museo8bits.com/z_minisport.htm Full specification and photographs (in Spanish)]
* [http://www.digibarn.com/collections/systems/zenith-minisport/index.html Lots of documentation and photographs (in English)]
* [http://www.qrz.com/download/library/mlhacker.zip Newsletters on the MiniSport Laptop Hacker (ZIP-file, documents in English)]