To prove why this book is still relevant, look at how Schwartz explains FM threshold.
Most modern books say: "Below a certain SNR, FM gets worse than AM." Schwartz actually calculates it. He shows you the phasor diagram of the carrier plus noise, the "click" phenomenon, and exactly why your FM radio hisses when you go through a tunnel. To prove why this book is still relevant,
If you are designing a low-power IoT device today, understanding that threshold is the difference between a working link and a dead battery. If you are designing a low-power IoT device
You might ask: “Why read a book published in 1970 (with later editions) when I can learn about QAM-256 from a website?” the "click" phenomenon
Here is the answer: Trends fade, but fundamentals do not.
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