This is a simple tubed mixer from the 50's. The circuit does not include the power supply and has 3 inputs with independent controls. The tubes are double and the inputs are high impedance.
This two-transistor constant current source is from a 1968 documentation. Modern equivalent...
This circuit was obtained in a 1977 technical documentation. The PUT admits equivalent and the...
We found this circuit in a 1997 documentation. Its purpose is to turn a load on or off using...