The KLA Tencor Alphastep profilometer measures step heights, surface profiles and roughness using a stylus with a 12.5um radius tip. Step heights can range from 20nm to 160um, with scan lengths up to 10mm. The stylus force is set to 18mg. Sporting a Z80 processor and a delightfully retro cathode ray tube, this classic tool is as useful now as it was in 1989. And like 99% of all Alphasteps, the printer stopped working in 1990.