Introduction: Light Bulb Flasher Without Transistors
There are many LightBulb/LED flashing circuits on the internet, but almost all of them use transistors or ICs. The idea of this instructable is to make a light bulb flasher without any transistors or ICs.
Step 1: Watch the Video!
Step 2: Get Components for This Project
- 12V relay with NO and NC contacts.
- 2200uF capacitor (16V or higher).
- 100 Ohms resistor 0.25W
Step 3: Build Everything According to the Circuit
Step 4: Connect It to a Power Source and Test It.
You need to connect it to 12V - 15V DC power source. It could be a car or a motorcycle battery or a 12V DC power supply.
Step 5: If It Works Unreliably, Add Capacitor and Resistor (if Necessary)
Sometimes this circuit doesn't work well with some relays.
To improve stability add sequentially connected resistor and capacitor between "NC contacts" and "common pin" of the relay, according to the circuit.
You will need 10 Ohms resistor and 470uF capacitor.