This simple circuit for headphones or small speakers was found in documentation from the 90s. The circuit works with voltages from 5 to 9 V and has good gain.
The component used in this circuit is uncommon today, as the circuit was obtained from Motorola's Linear...
This simulated circuit on the NI Multisim transmits modulated infrared signals with the audio...
This voltage sensor limits the discharge of a Nicad battery. We found it in an American...