The indicator for this circuit is a 0 to 1 mA milliammeter. The operational is from the 70s, when the circuit was published. Modern equivalent can be used.
This circuit is from the Motorola Linear Databook of 1990. The circuit controls a Triac from a...
The circuit shown uses the LM324, but can be implemented with other operational ones. The source...
This circuit makes use of a stroboscopic tube, a component that no longer exists today. The...