- on Power Supplies
- Published in issue 6/2003 on page 0
Need DC Power? Try a PC/AT supply?
Modifications for non-standard output voltages
Although the amount of power drawn by electronic circuits is steadily decreasing, there are still many devices that need a large amount of lowvoltage power. Some examples are miniature (PCB) drills, model railways, vintage radios, safe low-voltage lighting and heating systems, battery chargers and so on. With a few modifications, a standard PC/AT supply is an excellent choice for the job.When they need a low-voltage power supply, most hobbyists use the ‘classic’ transformer/bridge rectifier combination. This has many advantages, such as simple design, outstanding mains isolation, robustness and low interference levels. However, there are also a few serious disadvantages to this approach: the supply is large and heavy, it is difficult to efficiently obtain an adjustable voltage at high power levels, and it is fairly expensive.