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.
Found in Radio Electronics from the 90s, this circuit has a power given by the output amplifier. The...
This circuit was obtained in a 1982 English magazine. The purpose of this circuit is to interface...
We found this circuit in an English publication of 1976. It can be easily assembled by changing the...