You will need
- - 8 galvanic cells;
- - 10 small batteries;
- - network step-down transformer at 12 Volts;
- - a power cord;
- - connecting wires.
To obtain a DC voltage of 12 Volts from the battery cells connect in series in the circuit of the 8 pieces. Connect the positive output of one element to the negative terminal of the next. Two extreme output of the resulting battery, connect to the consumer current. Observe the correct polarity. For more total battery power collect a single battery of 8 cells. Then connect the battery in parallel. To do this, connect only the extreme conclusions of a single battery to each other, plus insights to the positive the terminal of the other battery, negative to negative conclusions.
To obtain a voltage source of 12 Volts from a small Nickel–cadmium or Nickel–metal hydride batteries connect them in series in a circuit of 10 pieces, since, in contrast to galvanic cells, batteries develop a voltage of 1.2 Volts. To connect the batteries must be the same as battery cells. The advantage of batteries is that they have greater capacity and are reusable sources of power.
To receive the AC source voltage is 12 Volts use the AC step-down transformer with voltage on the secondary winding to 12 Volts. Connect the power cord to the primary winding of the transformer. A consumer AC connect to the secondary (output) winding of the transformer. The transformer must provide a current exceeding the maximum load by 30%.
This voltage can be obtained from 12 volts DC by using simple circuits, which are based on a particular voltage regulator. For normal operation of the stabilizer it is necessary to provide him with a heat sink. Overheating significantly reduces the output current, and in the end, the stabilizer will simply burn.
For example, many well known and widely used power supply electronics D2-27 is unregulated and has output of 12 volts. Unregulated power supplies are all the chargers for cell telephones, adapters, modems and routers. They are usually designed for one output voltage: 5 , 9, 10, or 12 volts.