Since the Spectrum had limited RAM (often 48K), specialized software like Copy Copy (1984) would load as much data as possible into the computer's memory, then ask the user to swap the original tape for a blank one to "dump" the data back out.
Once the speed and encoding method were identified, the software could read the data blocks directly into the RAM. Crucially, it stored this data not as a functional program, but as a raw memory image.
Whether you’re archiving a box of old cassettes or simply curious how a 48KB machine could clone itself, the answer lies in those tight Z80 timing loops. And the good news: with an emulator and a few .TZX files, you can see that exact copy software working right now—just as it did in 1985. zx copy software work
, this was a top-tier utility for transferring tape-based software to the more reliable Sinclair ZX Microdrive or +3 disk system. Multiface Hardware : While not software-only, the Multiface 1
These were specialized "tape-to-tape" copiers. TFCopy (Tape-File Copy) was famous for its "full memory" mode, which utilized the Spectrum's video RAM (the area used to display the screen) to squeeze in larger programs during the copy process. Since the Spectrum had limited RAM (often 48K),
: To fight these utilities, publishers moved away from software-based protection and toward physical "dongles" like the Lenslok —a plastic prism you had to hold up to the TV to read a scrambled code.
As copy software became sophisticated, publishers responded with advanced protections like and Alkatraz . These systems utilized self-modifying code and intricate timing checks. Whether you’re archiving a box of old cassettes
There is also a modern open-source tool called Universal Pokemon Randomizer ZX which, while sharing the "ZX" name, is a modding tool for Pokémon ROMs rather than a Sinclair utility.