This circuit was found in American documentation from the 90's. The circuit applies to any operational. The power supply can be between 5 and 15 V depending on the operational.
Using an integrated circuit from the time, this circuit was found in Radio Electronics from the...
This shield circuit is from old documentation. The operational amplifier used is not common today...
This circuit powers a small 5 W lamp that goes out when power is lost. The circuit can use the...