Electro-mechanical watch movement
In a quartz movement a crystal is made to vibrate in electrical oscillations. The frequency is then divided down to one cycle per second, detected visually by jerkily moving the seconds hand. The second step is transfered with a tiny motor to the gear train.
In principle quartz movements run more accurate than mechanical movements, however they mostly need batteries.
Today, quartz movements are to be found mainly in watches of the lower price ranges and in most women's watches.
Early Quartz Movements
- Beta 21 (1967-1972)
- Longines Ultra-Quartz Cal. 6512 (1969-1972) - first quartz movement announced for production but was delayed by over two years
- Seiko Cal. 35A (1969-1970) - The original Seiko Astron movement
- Girard-Perregaux Elcron Cal. 352 (1970-) - 32 KHz with stepper motor, also used by Jaeger-LeCoultre as the Master-Quartz and Favre-Leuba
- Cal. 353 was thicker and used a thicker battery
- Seiko Cal. 38 (1971-) - Advanced quartz movement with stepper motor, first mass-produced quartz movement from Seiko
- Ronda 1377 (1973-) - Ronda partnered with Motorola to deliver an in-house movement
- Omega 1310 (1972-) - Omega's first in-house quartz movement, 32 KHz
- Omega 1510 Megaquartz (1973-) - Omega's high-frequency quartz movement, 2.4 MHz
- ESA 9180 (1972-) - ETA's first in-house integrated quartz movement with a stepper motor
- Seiko Cal. 39 (1974) - Includes an LED module to "tick" with the seconds hand
- Seiko 0903 (1975) - Seiko's third-generation quartz module