I've found "Big Clive" to be very informative. Lots of small devices torn down and reverse engineered, complete with a circuit diagram and a fairly in depth exp

I've found "Big Clive" to be very informative. Lots of small devices torn down and reverse engineered, complete with a circuit diagram and a fairly in depth explanation of what is going on and what any given part is doing. Helps to have some basic circuits knowledge, but otherwise very good.