 Some companies outside the US and UK produced their own " pirate " versions of the ZX81 and Timex Sinclair computers , aided by weak intellectual property laws in their countries of origin . Several Brazilian companies produced ZX81 clones , notably the TK series ( such as the <unk> ) from <unk> Eletronica of Brazil ) and <unk> 's CP @-@ 200 . <unk> Eletronica of Argentina produced the <unk> and <unk> , clones of the ZX81 and <unk> respectively . Lambda Electronics of Hong Kong produced the Lambda 3000 , based on the ZX81 , which was itself widely copied by other Chinese manufacturers . 
