pll systems

It is the intention of this article to give an introduction to Phase- Locked- Loop ( P L L) systems, without assuming any advanced mathematical knowledge on behalf of the reader, nor any familiarity with the subject. - The need for such an introduction stems from the ever-increasing use of PLL circuits in consumer electronics and from the increasing complexity of these circuits, which is threatening to make new developments in this field incomprehensible to many electronics enthusiasts. The article also deals with Feedback PLL systems, which are in many ways superior to conventional PLL circuits. A simple receiver using the Feedback PLL principle will be described in a future issue