This circuit is from an American documentation from 1975. The single junction transistors can be 2N2646 and the signal must be applied to the input of a good amplifier.
This is a bridge for the measurement of low value resistances and high values too. The circuit...
This inverter bistable buffer circuit was obtained in a Hands On of the 90's. Next to the circuit we...
Other series amplifiers such as the MC3301, MC3401 and LM2900 can be used on this circuit. We...