This tone control was obtained in a Signetics documentation of the 90s. The integrated circuit can be practically any operational amplifier. The power supply is symmetrical.
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...