Although dealing with all models from M/742 through M/1206 manufactured from 1963 to 1981, this book specifically covers the four basic types of Bally machines: Single coin, five coin multiplier, three-line and five-line criss-cross. However, the knowledge gained from this book will enable the reader to work on a great many other Bally machines. Over 300 detailed photographs, 94 isolated circuit diagrams and four complete, large, fold-out schematics (printed on colored paper for ease in locating) for the four basic types are accompanied by step-by-step instructions for all routine maintenance operations, as well as complete assembly, disassembly, overhaul, lubrication and theory of operation. The book is organized into 17 chapters with six appendices. Methods used to calculate payout characteristics have been demonstrated, so the statistics of any machine can be computed by the reader. Additionally, there is a detailed lubrication guide specifying the precise location and type of lubricants required on the various assemblies. A comprehensive trouble-shooting guide is included for routine, easy-to-fix malfunctions. Throughout the book are numerous charts, tables and diagrams, each electrical diagram contains location codes for the electrical components so that they can easily be found. This extraordinary full-size book has been written specifically for the person who is a novice with electricity and has had no prior training in the mechanics of slot machines. This approach allows the reader to become comfortable with the simple circuits (and their mechanical interfaces) used in the Bally electro-mechanical slot machines. Thus, with a few simple tools you'll be able to analyze and correct any problem you may encounter with your Bally machine. 224 Pgs 1994