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.
The circuit presented is an interface or shield for capacitance measurement as a PC. We found it...
This circuit uses two transistors, the low noise BC549. Its quality is very good and it has a...
The idea of this simple circuit is to use a tape recorder to key a transmitter in code emission....