We found this circuit in an American documentation from the 90's. The circuit makes use of general purpose NPN transistors. The 0.005 uF (5nF) capacitors determine the frequency.
This voltage controlled oscillator, which can be used as a shield, generates signals in the 1.5...
This circuit was obtained from the 1976 Siemens integrated circuits manual. It is the circuit for...
This instrumentation circuit was found in the September 1989 Radio Electronics magazine. The...