Program Link | Zx Spectrum Test

It uses the border color to signal error codes if the main screen memory is corrupted.

If you just want to see what the program does before burning an EPROM: zx spectrum test program link

Replace the flexible plastic keyboard membrane inside the case. It uses the border color to signal error

2. The Official Sinclair Test Program (The Horizon / Factory Test) zx spectrum test program link

ULA chip is failing or overheating. Consider a vLA81 replacement.