The quartz watch and electronics in modern watches
Crystal, circuit and stepper motor in practice
Most watches sold today have a quartz movement. Where the mechanical watch movement is a pure mechanical chain, the quartz watch is a small electronic machine where a battery, a circuit and a motor work together to move the hands. For a modern watchmaker, mastering this technology is just as important as classical mechanics, because most customers who walk in the door own a quartz watch.
§The quartz crystal as timekeeper
The heart of a quartz watch is a small crystal of quartz that is cut to have a very stable oscillation frequency. The crystal uses the so-called piezoelectric effect: when an electrical voltage is applied to it, it oscillates at a frequency that is far more stable than any mechanical balance wheel can achieve. It is this stability that makes the quartz watch significantly more accurate than the mechanical watch in everyday use.
§From oscillation to pointer movement
- 01The crystal vibrates at its fixed, high frequency when it receives power from the battery
- 02An integrated circuit (IC) counts and divides the oscillations down to exactly one signal per second
- 03The signal is sent to a small stepper motor, which rotates a gear system exactly one step at a time
- 04The gear system drives the hands so the second hand typically jumps one clear step each second
§The power source: the button cell battery
Because the stepper motor and circuit use very little power per pulse, a small button cell battery can keep an ordinary quartz watch running for typically one to two years, depending on the watch's functions. Silver oxide batteries (marked SR) are often used in classic analogue watches because they maintain stable voltage for most of their lifetime, while lithium batteries (CR) are often chosen for watches with more functions or higher power consumption, such as those with light or alarms.
§Troubleshooting on electronic watches
Where on a mechanical watch you look for wear, dried oil or a bent part, on a quartz watch you look for electrical faults. The watchmaker uses measuring equipment such as a multimeter to check the coil, contact springs and circuit for corrosion, breakage or short circuit. If the integrated circuit itself is faulty, it can rarely be repaired in detail — in practice the entire watch module is often replaced together because it is not worthwhile to repair individual components on such a densely packed circuit.
§Hybrid and special watches
Some modern watches combine the best of both worlds: a classic hands-on look with electronic control in the background, e.g. watches that automatically synchronize time via radio signal or GPS or watches with quartz-controlled extra functions like alarm and stopwatch. For the watchmaker this means the trade's electronic part is constantly evolving and curiosity about new technology is as important as classic craftsmanship.
| Property | Mechanical | Quartz |
|---|---|---|
| Precision | Typically a few seconds per day depending on calibre and adjustment | Typically under half a second per day |
| Energy source | Drawn spring (manual or automatic) | Button cell battery |
| Maintenance | Must be cleaned and lubricated at regular intervals | Battery replacement and occasional inspection |
| Repair | Parts can be cleaned, adjusted and replaced individually | Faulty circuits are often replaced as a complete module |
Neither of the two technologies makes the other obsolete. Customers still demand both — some for precision and convenience others for the craft and tradition in the mechanical watch. An all-round watchmaker can talk to the customer about both and service them equally professionally.