Many electrical devices use alternating current, or AC electrical energy. This type of electrical energy can be applied across an electrical transformer to increase or decrease the voltage of the AC signal. However, many consumer electronics (such as cell phone chargers and laptop computers) require direct current, or DC electrical energy. To convert alternating current electrical energy to direct current electrical energy, the AC signal must pass through a set of electronic components called diodes. Diodes act as an electrical check valve by allowing electrical current to flow in one direction only.
Cut six pieces of wire, and strip a half-inch of insulation from each wire end. Place one of the ring terminals over one end of the first piece of wire. Place the other ring terminal over one end of the second piece of wire.
Twist the free end of the first piece of wire together with the cathode leads on the first and second diodes. Solder this connection.
Twist together the free end of the second piece of wire together with the anode leads on the third and fourth diodes. Solder this electrical connection.
Twist together one end of the third wire jointly with the anode lead from the first diode, and with the cathode lead from the third diode. Solder this connection.
Twist together one end of the fourth wire jointly with the anode lead from the second diode, and with the cathode lead from the fourth diode. Solder this electrical connection.
Attach the free end of the third wire to one of the power terminals on the AC power supply. Attach the free end of the fourth wire to the other power terminal on the AC power supply.
The ring terminal at the end of the first wire is the positive lead. The ring terminal at the end of the second wire is the negative lead. The voltage differential between the ring terminals is 12 Volts DC.