This Engineer's Mini Notebook features more than two dozen 555 timer circuits that you can build, 50 operational amplifier (OpAmp) circuits, and a wide range of optoelectronic circuits and projects, including many LED and lightwave circuits. This is a compilation of three of Mims's best-selling notebooks: 555 Timer IC Circuits; OpAmp Projects; and Optoelectronics. Forrest M. Mims, III, has written dozens of books, hundreds of articles, invented scientific devices, and travelled to the Amazon for NASA. He loves to share his knowledge with eager students! Used Book in Good Condition