This simple bridge circuit can be used for impedance or resistance measurement using a high impedance earphone as an indicator. The circuit is from an American 80's documentation.
This circuit, from a 2002 documentation, checks the logic levels of the inputs, providing a...
This circuit can be used to measure the frequency of a low frequency square signal. The signal can be...
Found in a 90’s Popular Electronics, this circuit uses a component that can be difficult to obtain...