I have a Belkin phone charger and I have noticed that every time I disconnect the phone, It makes a series of strange noises, a high pitched one, a low pitched one and then it continues making a high pitched sound. I know that the transformer is making these sounds but, why does it make that...
I will admit from the git-go that i am almost totally electronically illiterate. So please factor that into any responce.
Here is what i am trying to accomplish. I would like to use a toy steam engine dynamo to power a USB port for the purpose of charging phones etc.
Here is a link to a...