Eric Zepler’s classic book The Technique of Radio Design was publised in two editions, in 1943 and 1945.

The relevant circuit theory was covered in the first chapter, and the rest of the book was devoted to the design of radios for industrial production. The operation and importance of negative feedback were explained in the third chapter. Later on there were thorough expositions of the problems of noise and distortion, and of undesired feedback in all its manifestations. The chapter on the principles of screening was a masterpiece.

This book was unique when it was published, because no books yet existed that covered the same material. Consequently there was no bibliography.

If you read this book you will appreciate Eric Zepler’s exceptional engineering ability. There was no guesswork. Every part of the design of a radio was based on the laws of physics, and was quantified and calculated. When Greville read the book he remember Zepler explaining at a blackboard how radio circuits should be designed.