The circuit analysis was technician-level but the concepts were illustrated with actual ‘scope circuitry to such depth that an engineer could be drawn in by it. Perhaps the book was written in part by Tek founder and creative engineer, Howard Vollum; no authorship is ascribed to it. Example pages are shown below.
In the era of this book, Tek also published two series of paperback books with similar style, one on circuit concepts and the other on measurement concepts. These books looked like they were typed; the font was courier and the right margin was not justified. The drawings were neat but plain. The books I have of these series were published in the late 60s or early 70s. They are presently available in PDF for download from David DiGiacomo; Test Equipment and Electronics Information.
During this time and thereafter, a large number of quite useful paperback publications appeared from what were mainly semiconductor companies. Most prominent was the library of useful paperback volumes that came from National Semiconductor Co., not the least of which was the classic Linear Applications Handbook. My copy is the 1986 edition and it has 1222 pages full of useful circuit applications. Earlier, Signetics published a white hardback classic with a mix of circuit applications. For both books, ICs of the companies would figure prominently, of course. Linear Technology, Analog Devices, and TI continued this tradition of maintaining a well-informed customer base. These companies have made available far more engineering literature than was necessary to sell parts, and the electronics engineering world is enriched by them through it to an extent hard to quantify.
This newer generation of industrial electronics literature has replaced the Rider-Sams-Gernsbach era of electronics material, beginning perhaps with the GE Transistor Manual, a classic transitional example. (Predating it was the RCA Radiotron Designer's Handbook, an electron-tube classic, downloadable from the Internet. With the ease of producing publication-quality script on an ordinary laptop computer, anyone who can write can become a self-publishing purveyor of electronics literature. Much of it has appeared on that great communications outlet of the current era, the Web, thereby replacing the magazine rack and even bookstores to an extent. Although material of varying quality has always appeared in the dominating media, today the Internet increases the scale to where greater effort must be paid in finding the better material.