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 is from the 1990 Motorola Data Databook. The circuit can be implemented with...
This circuit can also be used as a simple thermoscope (temperature changes indicator) in the...
This circuit allows you to program a resistance by combining the selected resistors. The circuit...