We found this circuit in a Popular Electronics from the 90s. It operates at a frequency of 15 kHz. Components can be difficult to obtain, such as the integrated circuit.
This circuit allows to increase the output power of a 741 as an amplifier. The circuit is from a...
This high voltage circuit was found in a 2005 Linear Technology application manual. The circuit...
This circuit for multiple sound inputs was found in a Radio Electronics from January 1992. It...