A book about amps, volts and the like. Name?

Question

Books

Guys, please tell me the name of the book.
A picture book about Dunno (for some reason I remember Dunno or there was some kind of boy in a big hat), about how he came (or didn’t go) to his grandfather and he began to tell him what current, amperes, etc.
This book is for dummies.

Answer 1

Not "Radio? .. It's very simple!" whether?