Timekeeper (U.S. Patent No. 3,895,486) W. Hammer, E. Vittoz, J. Hermann, H. Choffat, 1975

Patented in 1975, Eric Vittoz's "Timekeeper" was comprised of a quartz crystal resonator with a stable frequency and a relatively large tolerance, and a frequency divider with an adjustable division ratio. This divider had auxiliary electrical inputs whose logical state determined the division ratio, and an electrically alterable electronic memory that supplyied stored data to determine the logical state of the auxiliary inputs and the division ratio. The SSCS News provides pages 1-2 of this patent.