I have the situation where 12v is either on continuously (or off), or on/off at the rate of once per second.
The 12v is from a car battery.
I want a circuit, to operate a relay that will switch according to whether the 12v is "square waving" or not.
I'm having trouble getting my head round what sort of RC circuit could drive the relay coil (about 270 ohms) to acieve that without resorting to transistors or chips.
The 12v is from a car battery.
I want a circuit, to operate a relay that will switch according to whether the 12v is "square waving" or not.
I'm having trouble getting my head round what sort of RC circuit could drive the relay coil (about 270 ohms) to acieve that without resorting to transistors or chips.