We found this circuit in the July 1994 Radio Electronics magazine. The circuit uses a general-purpose transistor, and the power supply can be up to 12 V depending on the relay.
According to its author, this device indicates the amount of force applied to the sensors. The...
This low frequency doubler requires a 50 mV signal at the input. The circuit is from an old...
This is a circuit that should not be used for readers interested in a fair game. The circuit...