How Quartz Watches Work

Before Quartz

The wind-up watch is an amazing piece of technology itself! It is part of a continuous research-and-development effort that started at the end of the 14th Century. Over the years, different innovations made wind-up watches smaller, thinner, more reliable, more accurate and even self-winding!

The components that you find in today's wind-up watches have been around for centuries:

  • A spring to provide the power
  • Some sort of oscillating mass to provide a timebase
  • Two or more hands
  • An enumerated dial on the face of the watch
  • Gears to slow down from the ticking rate of the oscillating mass and connect the mass and spring to the hands on the dial

See How Pendulum Clocks Work for a description of these different parts.

By the end of the 1960s, the Bulova watch company made the first step away from the oscillating balance wheel -- it used a transistor oscillator that maintained a tuning fork. This watch hummed at some hundreds of hertz (Hz, cycles per second) rather than ticking! Cogs and wheels still converted the mechanical movement of the tuning fork to movement of the hands, but two major steps had been taken:

  1. The replacement of the balance wheel and spring with a single-material resonator: the tuning fork
  2. The replacement of the wind-up main spring with a battery

A watch-making company in the late 1960s was bound to look for the next step -- a technology that would give even better time keeping than the tuning fork. Integrated circuits were very new at the time, but the price was dropping rapidly and the number of transistors was growing. LEDs were also new on the scene. There were still a couple of problems to be solved: finding a new timing element and designing an integrated circuit that would use very little power to allow the watch to run on a tiny internal battery.