This circuit was found in the March 1980 issue of Radio Electronics magazine. It is based on the newly released LH2400. The circuit must be powered by a symmetrical power supply.
This circuit generates sinusoidal signals between 300 and 3000 Hz. We find a 303 Circuits from the 90's....
This amplifier for audio transmission lines was found in a 1961 American publication. The critical...
Old phones with dials can be used in a simple home intercom system, as this circuit from Popular...