This 1974 circuit uses two 555 integrated circuits in a very traditional configuration. The circuit can be powered by voltages from 9 to 12 V and for greater volume an amplifier stage can be added.
This is a bridge for the measurement of low value resistances and high values too. The circuit...
This circuit was found in Radio Electronics magazine from April 1961. The device has a slot for...
We found this circuit in an English publication. The transistor can be a BC558. The instrument can be...