2. Alternating signal generation

It's relatively easy to create an energy source with a constant output. This is the case of the battery in electricity. On the other hand, creating a source with periodic output requires an additional mechanism to convert a DC signal into an AC signal. In the case of the dynamo, the energy expended continuously by the cyclist and producing uniform motion is converted into an electrical signal with a period related to the speed of rotation of the wheel and dynamo. The following paragraphs describe the various mechanisms for converting a DC signal into an AC signal.