This circuit uses only transistors and was found in a 2003 documentation. Transistor 2N3055 must be mounted on a heat sink and the voltage is set to R10.
The figure shows three circuits for using headphones in amplifiers with speakers that do not have...
In this charger, the charging current is basically limited by the LEDs. The transformer is a low...
This configuration is from an old integrated circuit manual. The circuit can be applied to modern...