The Nascom 2 was a deep evolution of the Nascom 1 that required 18 months of design and development but offered lots of enhancements: a faster processor (4 MHZ.), greater RAM and ROM capacity (10 KB + 10 KB), built-in Microsoft BASIC, extended keyboard, improved tape interface, etc.
User RAM could be expanded to 32 KB on board and the system didn't need the use of expansion board or system bus to run large applications. Even now, the Nascom 2 is regarded as the most versatile single board computer in 1980's.
Sadly, in 1980, Nascom Limited company met difficulties in components sourcing, specially RAM chips, and the company ceased Nascom 2 deliveries. Some Nascom dealers will then set up the Gemini company and produce a copy of the Nascom 2. Finally, Nascom Limited is sold to Lucas Logic (later Lucas Nascom) in 1982 and the Nascom 2 will come back in a cased version called Nascom 3.
I started with a Nascom 1 in 1978, upgraded to a Nascom 2, and added a Z80B based Gemini display card, two 256K RAM boards, floppy disc board with two 5.25" drives, I/O board, sound card with two sneaky copies of the Winchester sound card, a floating-point add-on processor card, and a Pluto colour graphics card with added palette card. I called it Marvin.