ZX Nucleon 512KB ver. 5.1 - NEW 5.1 (2025 year) VERSION

Pentagon 512KB (~fast ZX Spectrum 128KB) clone

Self, home-made electronic kit. Contains PCB with all pre-soldered SMDs, all electronic components, printed paper documentation

Real photos

The PCB dimensions correspond to the ZX Spectrum 48KB board and is intended for its case.

Pentagon, respectively Nucleon computers is the ZX Spectrum clones, but with some important differences. The main difference is that the Pentagon, respectively Nucleon does not know how to divide RAM into a slow and fast part, just like the original ZX Spectrum, all RAM is fast, The CPU is not stopped in any part of RAM. There is also a difference in timing, screen generation, interrupt generation, etc. Now these differences are calculated in a huge number of programs that arise from the 90s in the countries of the former Soviet Union, and that the vast majority do not work on the original ZX Spectrum correctly. This was the reason for the ZX Nucleon project. Detailed information about Pentagon computers is available on the Internet and will not be discussed here.

The new 5.1 version of the board from 2025 brings four major changes compared to the older board generation:

1. Three selectable video signal formats are now available - composite video, S-VHS, analog RGB
2. RAM memory chip changed to modern SMD version
3. Optional two ROM versions: Nucleon ROM (with TR-DOS support) vs classic 128s +2 ROM
4. The Megaprojects Ltd association now takes care of the management of the device and its distribution

More videos of the ZX Nucleon construction can be seen on YouTube, please enter the term "ZX Nucleon" in the YT search.