This circuit is designed to measure very weak currents, in the order of picoamperes. We found it in an American documentation from the 80s. The integrated circuit is from that time.
This circuit produces a loud sound in the speaker when water level reaches the sensor. The power...
May 2016 - It can be obtained from Mouser Electronics new display 1092 from VDC. The new LED...
This Motorola circuit is from 1965. Collector currents must be 7 and 12 A for transistors....