This circuit produces a signal when the turn signal is on, preventing it from being forgotten in this condition. The circuit was found in a Popular Electronics from the 80s.
This circuit makes use of an operational amplifier from the 80's. The circuit can be implemented with...
When the power is cut off, this circuit keeps the flashlight on for a while, allowing it to be...
Using the CK722 this directional photometer was published in Radio Electronics magazine in July...