RC car starting light circuit.

Thread Starter


Joined Mar 19, 2016
Hi there.
My son has been playing around with his rc cars lately and racing with friends. I was looking to make up a starting light set up for him. I have access to a heap of red and green LED lights and 12v relays. I was hoping to make something battery powered so he can move it around when they go out. I would like the circuit to have 3 red lights and 1 green. Hit a start button and the 1st led comes on and stays on. 1 second later the 2nd comes on and stays on. 1 second later the 3rd comes on and stays on. 1 second later the 4th (green) comes on and simultainously turns off the 3 other red lights. I hope that makes sense. Basically looking to do it as "cost effectivly" as possible. My basic knowledge has me doing it with 2 relays and 3 timers. Can anyone give me suggestion on how to do it with 1 timer or some sort of board i could order to make it. Hope it all makes sense. Thanks in advance. Have attatched a photo of a quick sketch of the circuit i was thinking.



Joined Sep 17, 2013
Welcome to AAC!
You could base a timer design on a CD4017 plus some logic, or you could use a microprocessor-based timer. The timer would drive some FETs to turn on the lights. Do you have a spec for the LEDs?