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Published by Noble Publishing Corporation, Atlanta GA 24085. First edition, 2000, 778 pages including the index, hardcover, 9¼ × 6¼ inches, B&W illustrations. ISBN 1-884932-07-X. Available from ARRL, 225 Main Street, Newington, CT 06111-1494, USA. ARRL Order No. RRCD, $89 plus shipping/handling. Order toll-free 1-888-277-5289 or QUICK ORDER online.
Review by Doug Smith, KF6DX
QEX Editor
(from July/Aug 2001 QEX)
Receiver design is a demanding endeavor that involves many variables. Interaction of those variables creates a complex choreography that can be difficult to manage without sufficient knowledge, experience and planning. McClaning and Vito are two engineers who have obviously been through it a few times and in their new book, they impart some of their collective wisdom, especially focusing on what works and what doesn't.
Radio Receiver Design covers contemporary implementations of many, but not all, critical receiver subsystems. Notably absent is detail about modern frequency synthesis techniques, although a chapter on oscillators and direct digital synthesis is included. The authors provide almost no information about control systems or DSP-based design. The material on AGC is too sparse to be useful to the neophyte, although common questions bout gain distribution and cascaded linearity performance are answered quite clearly.
The book begins with some definitions and heads rapidly into a discussion of transmission-line, matching, and modulation theories. Significant is the statement that source-matched amplifiers cannot have an efficiency exceeding 50%. That is: When an amplifier's source impedance is equal to its load impedance, all available power is delivered to the load; but only half the power is available compared to that of an amplifier having a low source resistance.
Examples, sanity checks and "war stories" are liberally employed to aid comprehension. Enough mathematics is retained to make this work an outstanding reference without bogging down the flow. Sometimes, though, the information is a little off-target for full understanding.
Instances of that are found mainly in the introductory chapter during the treatment of modulation. Fig 1-47 depicts a real sine wave as a single phasor, rotating in the complex plane; a better representation would be two phasors rotating in opposite directions. That is corrected later in the chapter when vectors for AM are brought in (Fig 1-71). SSB is not discussed at all. When explaining PM waves, the mathematical descriptions are correct, but the authors sometimes imply an unintended meaning. For example, they state on p 126 that the envelope of FM and PM waves is always constant; in their mention of occupied bandwidth that immediately follows, though, they fail to point out that is only true when bandwidth is infinite.
The rest of the book is loaded with practical information and valuable insight about filters, amplifiers and mixers. You will find it a really good place to start if you are learning how to put those things together to build a receiver. It is well organized and well written. It is recommended for novice and intermediate-level engineers, students, experimenters and hobbyists. Kevin McClaning teaches at Johns Hopkins University and Tom Vito works for the US Department of Defense.
