Based on LM-317 voltage regulator. Can be used to control fan speeds, or as a light dimmer, or for creating custom chargers for batteries or phones etc or to power smaller circuit boards. Larger regulators can be bought for applications that draw higher loads. This LM317 will work up to about a 2 amps load. All parts are readily available on ebay or radioshack etc.
Small heatsink must be fitted to the LM-317 when higher loads are used.
Design based on the circuit in this video: [ Ссылка ]
![](https://s2.save4k.ru/pic/vaiqg7H0WvU/mqdefault.jpg)