lucas n3+drive a


Shown here on top of a Nascom-3 is the first version of the Lucas disk drive system. I don’t know how many were supplied in this cabinet.  It was first shown at an exhibition. I’d like a better photo of this if anyone has one.


The drives were TEAC TD50-C 77 single sided “double track density” 80-track 96TPI devices, which were mechanically incompatible with the existing Henelec/Gemini G805 and the Gemini G809/G815 systems.

Lucas used their own design of controller card. It used the NAS-BUS / 80-BUS for connection.

A design that definitely was eventually sold were the much simpler metal-cased side-by-side designs, which were re-badged Cumana units.


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Initially full height drives were used. These were single-sided 80- track units with a built-in power supply and were very heavy! (I know this as they were also supplied for some Commodore PET systems and I’ve had to pick one up!) They stored about 720k per drive.


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Later there was a much neater version using half-height drives.

Hardware Manual






A complete Nascom-Lucas system. Picture provided by Nick. Thanks! 🙂

These used the TEAC FD55 family of drives, and were available with either 350k or 720k per drive. The stepping rate was higher than that of the full height drives, which later versions of NAS-DOS took advantage of (causing some software problems with later software running on earlier drives).

In addition to NAS-DOS, CP/M 2.2 was also available for the Lucas system.


Nascom Pages