Луч Kварц ( Luch Quartz) is not a classic quartz watch with a stepper motor, this is the USSR version of the electro-mechanical watch with the balance wheel.
On the my site you can see a similar Swiss made model of BWC Transi Tronic that I presented and described how it works. The difference is that this USSR Luch has added quartz crystal that controls the operation of the electronic assembly, which gives impulse to change the polarity of the electromagnet below the balance wheel. This makes it significantly more accurate in operation.
This watch dates from the early 80’s, it is very interesting and the Soviets really tried to make it well.
