Radar watches use an oscillator circuit, which consists of an inductor (L) and a capacitor (C). The oscillator circuit is driven by a voltage source, such as a battery. This creates an oscillation in the circuit which alternates between an AC current and a DC current. The frequency of the oscillation is determined by the value of the inductor and capacitor.

The oscillator circuit drives an electric motor, which turns the hands of the watch. The frequency of the oscillator circuit determines the speed at which the hands move, and thus the accuracy of the watch. If the frequency is adjusted accurately, the watch's hands will move at a constant rate, giving it accurate timekeeping.

The frequency of the oscillator circuit can be adjusted by changing the value of the inductor or capacitor. This is done by placing a small adjustable dial on the back of the watch, usually marked with numbers from 0 to 9. By turning the dial, the inductor or capacitor is adjusted, changing the frequency of the oscillator circuit. This allows the wearer to adjust the time on the watch to keep it accurate.

In addition to being tuned with a dial, some watches may have buttons or sensors that can be used to adjust the frequency and sync the watch to a more accurate atomic clock signal. This signal helps keep the watch's time accurate to within a few seconds per day.

Overall, radar watches use an oscillator circuit to power the watch's movement and allow the wearer to adjust the time. By using an adjustable dial or a signal from an atomic clock, the frequency of the oscillator circuit can be adjusted to keep the watch's time accurate.