This low current source without a transformer is intended for applications where insulation is not important. The circuit has a 110 V (120 V) input and was found in old American documentation.
We found this circuit in a 1980s documentation. The circuit uses general purpose transistors,...
With this circuit it is possible to connect a low impedance microphone to the high impedance input...
We found this amplifier in a 90's manual. The integrated circuit is not easy to obtain today. The...