Since I cannot browse the live internet or access specific PDF files directly, here is a breakdown of the of the classic Elektor "300 Circuits" volumes (often referred to as "300 schakelingen" in Dutch or "300 Circuits" in English).
It seems you are looking for a or key characteristic of the book 300 Circuits (from Elektor Electronics).
Search Google for: Elektor 300 Circuits shop (look for the Elektor.com store).
I help teams achieve class-leading web performance, providing consultancy, guidance, and hands-on expertise.
I specialise in tackling complex, large-scale projects where speed, scalability, and reliability are critical to success.