This sensor circuit for currents of the order of nanoamperes was found in an American documentation from the 1980s. The components are from that time.
This is the conventional astable configuration of the 555 integrated circuit already explored in...
The maximum current of this circuit can reach 500 mA with BD136 and 1 A with TIP32. The circuit...
This circuit was found in a 1980s technical documentation. It tests the inverse characteristics of a high...