This activity operates red, amber and blooming LEDs in the actual arrangement for a distinct UK cartage light. The time taken for the complete red - red & amber - blooming - amber arrangement can be assorted from about 7s to about 2½ account by adjusting the 1M preset. Some amber LEDs afford ablaze that is about red so you may adopt to use a chicken LED.
|How to build Traffic Light Diagram|
|How to build Traffic Light DIagram|
The 555 astable ambit provides alarm pulses for the 4017 adverse which has ten outputs (Q0 to Q9). Each achievement becomes aerial in about-face as the alarm pulses are received. Appropriate outputs are accumulated with diodes to accumulation the amber and blooming LEDs. The red LED is affiliated to the ÷10 achievement which is aerial for the aboriginal 5 counts (Q0-Q4 high), this saves application 5 diodes for red and simplifies the circuit.
This activity uses a 555 astable ambit to accommodate the alarm pulses for the 4017 counter.
resistors: 470 ×3, 22k, 100k
capacitors: 0.1µF, 1µF 16V radial, 10µF 16V radial
diodes: 1N4148 ×6
LEDs: red, amber (or yellow), green
1M preset, horizontal
555 timer IC, such as NE555
4017 adverse IC
DIL sockets for ICs: 8-pin, 16-pin
battery blow for 9V PP3
stripboard: 20 rows × 21 holes