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The Electronics of Radio is a college-level textbook, and the author is a professor of electrical engineering at the California Institute of Technology. There is a good deal of mathematics in many of the chapters, and knowledge of basic first-year calculus would be helpful to understand some of the material.
This being the case, why would this book be of interest to many hams? Because there are some real goodies between the soft covers of an attractive, well-written text using the NorCal 40A QRP rig as its example.
The first chapter is a summary of radio--from the Titanic through basic electrical laws, receiver and transmitter components and stages, up to the NorCal rig. From this point onward the following chapters are more conventional--components, transmission lines, filters, amplifiers and so on. But included in here are any number of interesting sidelights and approaches. As an example of acoustics, in Chapter 7 there is a problem (or exercise for the student) using a resonate tube to change the response of a loud speaker. Anyone remember some of the old "Hints And Kinks?"
The oscillator chapter of The Electronics of Radio contains a very nice explanation of RIT, the NorCal circuit that generated this function, and a drawing of the components on the board to show how it is actually built. For those who like to see actual hardware along with theory, KN6EK often obliges.
Chapter 12 is devoted to mixers, and there is a bit of math used. However, for anyone who is tired of long and inconclusive discussions of mixers, spurious products and receiver problems, the material in this chapter is very much worth reading. Included is a very precise explanation of key clicks using a power spectrum expression --but with it is a filter and an explanation of the way the filter works.
The noise chapter a mathematically based explanation of what goes on in a receiver. Like it or not, this is an area where the math is needed to explain the operation. Although some calculus is used, unless you are an engineering student, you probably won't miss much by just passing over the calculus equations.
Chapter 15, Antennas And Propagation, contains a very nice section concerning the Friis Formula. Many technical people will recognize most of it as the radar range equation, used to predict how far a radar system can see a target. Along with it is an expla-nation of how to calculate line-of-sight for VHF, UHF and microwave is an explanation of why the Earth's radius is multiplied by 4/3 for calculating line-of-sight.
There are several appendices included. Appendix B goes through Fourier Series. But unlike the treatment in most math handbooks, this one is directed and limited to radio and electronics applications. The examples worked out in detail are for a square wave, rectified cosine (or sine) wave and narrow pulses.
Another appendix explains the use of Puff 2.1 and the disk accompanying the book. Puff 2.1 is a circuit simulator for linear circuits that also makes microstrip and stripline layouts. I did not attempt to use the software.
The final appendix is a very nice feature I appreciated both as a reader and teacher--a set of data sheets for the critical components used in The Electronics of Radio, as well as the Web addresses of many of the suppliers. Often you see a transistor or integrated circuit used in a technical discussion and you have no clue as to its characteristics. The appendix thankfully cures this problem.
In summary, The Electronics of Radio uses the novel approach of making a real ham rig as the subject of most of its examples. As a textbook, it is not general light reading for everyone, but it has a number of goodies in it, and if you want to see a slightly different approach to electronics, take a look at The Electronics of Radio.
