Tales from four decades in the Sinclair aftermarket: Parts, upgrades and party tricks

RWAP Software owner Rich Mellor talks ZX81 sound cards and linking USB printers to parallel ports
Retro Tech Week RWAP Software has been offering parts and upgrades for Sinclair Research computers since the mid-1980s. Owner Rich Mellor talked to El Reg about what got him into the business, what's kept him interested, as well as his new product – which is a very different beast.…