A fter watching this video from RMC I ordered some bits from ZXRenew; a new membrane keyboard and a couple of the modulator replacements. In the past I've used the ZX-CCB and thought I'd try the ZXRenew Composite Modulator Replacement . I knew that in my box of ZX81 parts I had one with a duff keyboard. It didn't really need that label because the connectors had obviously cracked and crumbled. Otherwise the case is in reasonable shape (the red ZX81 can be easily touched up). The board looks great. Most chips are in sockets and in the past I've obviously found the ULA to be good and heatsinked (heatsunk?) it. The other side of the board is a bit fluxy, but I think this is a 'bought assembled' one. The modulator was in good shape but pretty useless today. It's easy to remove it without damaging anything, and keep it somewhere safe. Here's the replacement in place. The switches determine whether the circuitry adds the 'backporch' to the video si