This circuit was found in the October 1994 issue of Electronics Now magazine. The 40446 IC is a PLL that is not very common today. The circuit has two types of effects.
This simulation shows how to use an operational amplifier as a voltage comparator. The sample uses the...
This circuit automatically activates the relay when the phone is answered, closing the record...
This car alarm was found in an American '80s documentation. The circuit automatically activates...