This episode of the Radio Design 101 series focuses on RF mixers, and on frequency conversion schemes commonly used in wireless hardware. 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 Episode 5 will cover some of the math behind mixing and discuss practical switching mixer circuits commonly used in radio hardware. As with other episodes in this series, this video 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 comm links.