The first working prototypes were ready in March 1966 and were presented to the press at the Osaka Fair of 1967. The Citizen X-8 Cosmotron was the first Japanese electronic watch. Its distinctive features are the four magnets on the balance and a single coil fixed on the pillar plate. Frequency 6 Hz.
| Citizen X-8 | |
| Chronometer cal. 0802, 0802, 0884. | |
| Chronomaster cal. 0820. | |
| Chronotron cal. 0840 and 0880. | |
| Date cal. 4840 (1969). | |
| Caliber 0811, 0830, 4830. | |
The Bulova Caravelle 12 OTC is the same movement as the Citizen 0811, the 12 OUC as the 0830, the 12 OUCD as the 4830.
| Citizen 5600 series, 1969. | |
| Caliber 5620 and 5650. | |
| Citizen IC 12 | |
| The Citizen 5800 series, the IC 12, 1970. Frequency 12 Hz. 5800 IC-12 Chronometer. 5810 and 5835 IC-12 Cosmotron with centre second. 5820 and 5830 without centre second. The movement has eight magnets fixed on the balance-wheel, two coils fixed on the pillar plate. This was an incredibly fast beating watch and the smallest transistorised ladies' watch at that time. | |
| Citizen 7800 Cosmotron, 1972. | |
| Four different calibers exist: 7800, 7801, 7803 A and the 7804 A. When the watch is held upright, date correction becomes possible, while held upside down day correction is possible. Frequency 6 Hz. | |
