The course of “Applied Electronics – Module 1” will describe some of the key elements that compose a modern telecommunication system. The course is structured in three separate units weighting 1 credit (c.f.u.) each, for a total of 3 credits. Each unit consist of a number of video lectures lasting in average thirty minutes each. The total duration of video lectures for the whole module is less than 15 hours. The topics covered in each unit are as follows. Unit 1: Basic concepts on the topologies adopted in linear power supplies, with some hints on the analysis and design of the circuits. Unit 2: RF frequency mixers, based both on passive and active devices. Definition of typical performance parameters. Unit 3: The phase locked loop (PLL) system: analysis and design. Digital PLL circuits. Main applications for PLL circuits.