The integrated circuit used in this 2002 project is not very common. It is powered directly by the telephone line, requiring no power supply.
This control circuit for incandescent lamps was found in a publication from the 90s. The circuit uses...
The power supply for this circuit must be symmetrical at 12 + 12 V and the load must be 8 ohms. The...
This practical two-transistor linear motor control idea was found in the September 1962 Radio...