Exatron Stringy Floppy (1978 – 1986)

The Exatron String Floppy was introduced in 1978, and was an endless loop tape cartridge system for microcomputers. At the time, floppy disk systems were still expensive, and cassette tapes were very slow. Despite the name, so-called stringy floppy systems are unrelated to floppy disks.

The tape cartridges, called wafers, contained a 1/16-inch loop of mylar-based chrome dioxide tape, in different lengths according to the capacity of the wafer. The smallest wafer contained 5 feet of tape and could hold 4 KB of data, and the longest was 75 foot and, capable of holding 64 KB of data. A 16 KB file took just 24 seconds to load.

The Exatron Stringy Floppy system was most commonly used with the TRS-80 range of computers, and did not require an expansion interface. By 1982, the price has fallen to $99.50. As well as being used to save data, software, including programs and games, was available on Stringy Floppy wafers.

Although popular with TRS-80 owners, the system could be unreliable, and as the price of faster and more reliable floppy disk drives fell they became less attractive. They continued to be advertised until 1986.

Similar stringy floppy tape systems were available during the 1980s, including the Sinclair ZX Microdrive, and the Rotronics Wafadrive.

Sources / Resources

ZX Microdrive (1983 – 1987)

The ZX Microdrive was a magnetic tape data storage format introduced in 1983 by Sinclair Research for use with its ZX Spectrum home computer, and later used on the Sinclair QL and ICL One Per Desk computers as a cheaper alternative to floppy disk drives.

It used a cartridge with an endless loop of very narrow (1.9mm wide) tape with a maximum capacity of 85 KB (when formatted for use in a QL, this was increased to 100 KB). The loop was 5 metres in length, and a complete circuit took 8 seconds.

Blank and pre-recorded cartridges were available.

The Wafadrive was a similar format also marketed to ZX Spectrum owners.

The ZX Microdrive system gained a reputation for unreliability, one of the reasons being tape stretch which meant the cartridges had a short lifespan. When used with the QL and ICL One Per Desk, the system was modified to reduce tape stretch.

The Sinclair QL was discontinued in 1986, and by 1987, the ZX Spectrum +3 was introduced that had a built-in 3-inch floppy disk drive.

Sources / Resources


Wafadrive (1984 – late 1980s)

The Wafadrive was a magnetic tape storage device for the Sinclair ZX Spectrum, released by Rotronics in 1984.

A Wafadrive unit had two drives, and the media are known as ‘wafas’. These used very narrow (1.8 mm) continuous loop tape,  and along with similar devices were nicknamed ‘stringy floppies’.

Wafadrives competed with Sinclair’s own ZX Microdrives, another type of stringy floppy device. Wafadrives were slower than ZX Microdrives, but still significantly faster than Compact Cassettes.

Wafas were available in 16 KB, 64 KB or 128 KB capacities and a few came preloaded with software.

Sources / Resources

Wikipedia entry for Wafadrive

The Spectrum Show Ep 2 on YouTube

Wafadrive information on DataServe Retro