Book dossier

Basic NEC with broadcast applications

by J. L. Smith

This book describes a new and almost unique tool for the radio engineer. It is a comprehensive document explaining and showing how to use NEC 2 to design directional AM broadcast antennas employing multiple excitation sources with field ratios as inputs. Basic NEC with Broadcast Applications addresses computer modeling of MF directional broadcast antennas and illustrates the assets and liabilities of the Numerical Electromagnetic Code (NEC). The book's how-to approach reveals the fundamentals of NEC operation, it teaches broadcast applications and shows the reader how to use NEC-2 to: model non-radiating networks, verify calculations, detune unused towers, design top-loaded and skirted antennas, minimize coding by moving and duplicating structures, and much more! The book is an invaluable toolkit for the design and analysis of broadcast antenna arrays. Apart from the very clearly and explicitly presented method of using NEC-2, the book includes a CD that demonstrates its use and provides a usable tool for directional antenna design. But it does not stop there. NEC -2 tends to be less than user friendly to the broadcaster therefore this book leads the user by the hand through the various steps in creating a broadcast directional antenna, and also makes it possible to fine tune an existing systems by investigating each portion of the design and achieving the best possible circuit values. Computer application is easy, does not require the use of Fortran, and the program runs happily on Windows XP. Included in this valuable book are many applications and test questions. The answers to these questions will be found on the CD together with explanations. It is obvious that the book was written by an engineer for the engineer engaged in the design and operation of directional antenna systems. NEC-2 was developed at Lawrence Livermore Laboratories and is commonly applied to antenna systems employing single excitation sources. It is a public domain program and can be downloaded from the internet free of charge. The methods described in this book can be used in connection with NEC-4 programming as well as NEC-2. The author has had a long broadcast career and entered the field in 1946. He later became Manager of Broadcast Systems Engineering for Collins Radio Company. He is now retired after participating in many FCC actions and international coordination projects.