Ed Nauman owns a house situated just uphill from some city-owned property that provides his yard with an endless supply of pocket gophers. He has tried to defeat them from digging up his yard, but ...

This circuit generates a tone that sounds very similar to a siren. The generator part of the circuit is made of the combination of PNP and NPN transistors. Toghether, the two transistors build up a ...

This is a simple circuit which produces a sound similar to the police siren and is built using NE555 Timer. Two 555 timers act as an astable multivibrator. Here is the simple circuit designed to ...