Jupiter ACE was a British home computer of the 1980s, marketed by a
company named Jupiter Cantab. The company was formed by Richard
Altwasser and Stephen Vickers, who had been on the design team for the
Sinclair ZX Spectrum.
Jupiter ACE somewhat resembled a ZX81 in a white case, with black
rubber keys like the Spectrum. It displayed output on a television, and
programs could be saved and loaded on cassette tape, as was standard at
that time. The machine came with 3 KB RAM, expandable to 49 K. It had
its own RAM packs, which are very rare and fetch high prices, however a
ZX81 Pack can be used with an adaptor.
The owner of this ACE has replaced the original case with one belonging to a Camputers Lynx. The extra space within the replacement has enabled the power supply to be incorporated and can be seen in the top right of the second image.