This episode focuses on radio frequency mixers, and on frequency conversion schemes commonly used in wireless hardware. As with other episodes in this series, it is based on and supports a university senior design course in which students design, build, test, and document real-world hardware such as FM broadcast-band receivers and FSK digital communication links. See the sites linked below for details on the associated course and for ways to construct circuits using the protoboards shown in the video. Starting with the basics, the process of up and down conversion is described and then demonstrated using a TinySA spectrum analyzer and a homebrew mixer built from an NE602 integrated circuit. Superheterodyne and direct conversion architectures are covered in some detail, and the video concludes with an examination of the dual conversion design used in modern spectrum analyzers. This is included in this Part 1 video. Part 2 of this episode will cover some of the math behind mixing and discuss several practical switching mixer circuits commonly used in radio hardware. More information is available at these sites: 1) Associated website: [ Ссылка ] 2) Overview of construction techniques: [ Ссылка ] 3) More on the prototyping boards used - including KiCad and Gerber files for fabrication (github site developed by an independent author): [ Ссылка ]
