Proa

The first IC used as a 1 second clock, which generates ON/OFF for the other ICs. Diodes help to cover the IC555 from the peak voltage. Take note that the relay used should have impedance more than 50 ohm.

Parts list :

•     Diode D1-D2 : 1N4001
•     Zener Diode D2 : 6V
•     R1,R5,R7 : 3k3
•     R2,R6,R8 : 68k
•     Resistor variable VR1 : 47k
•     Polar capacitor C1 : 10uF/16V
•     Polar capacitor C3,C5 : 2.2 uF/16V
•     Capacitor C2,C4,C6 : 0.01 uF
•     Transistor T1 : BC107/BC148
•     IC timer : NE555
•     Relay : 6-9 V
•     Power supply 6-9 V