Car turn indicator circuit

When the car turns, the direction indicator lights
flash one after another to indicate the direction of the turn, so as to draw
the attention of passing vehicles and pedestrians to their safety. The working principle of the car turning flash first
indicator circuit is as shown in the figure.
VT1 and VT2 form an astable circuit . When Sl
is closed, the astable circuit starts to work. Since VT1
is constantly on and off, the relay K is continuously turned on and off.
The suction and release make the indicator light circuit turn on and off, and
the light emits a flashing light. When S2 is closed on "l"
, the left light of the car will light up; when S2 is closed on "2"
, the indicator light on the right side of the car will light up.