This comprehensive guide outlines the design and construction of affordable DIY Nuclear Magnetic Resonance (NMR) spectrometers, offering an expert-level roadmap for various applications like education and process monitoring. It begins by explaining the fundamental principles of low-field NMR, including nuclear spin, Larmor frequency, and the process of signal detection. The text then details the inherent performance trade-offs in low-field systems, such as limited chemical shift dispersion, low sensitivity, and challenges with resolution, emphasizing the crucial role of magnetic field homogeneity. A significant portion focuses on the heart of the spectrometer, the magnet, discussing the infeasibility of superconducting magnets for DIY projects and promoting Halbach arrays and even Earth's magnetic field (EFNMR) as viable alternatives, alongside techniques for shimming and stabilization. Furthermore, the guide covers the essential NMR probe, explaining RF coil construction with Litz wire and the importance of tuning, matching, and the Transmit/Receive (T/R) switch. Finally, it describes various spectrometer console architectures—microcontroller-centric, Software-Defined Radio (SDR), and FPGA-based—along with open-source software solutions for instrument control and data analysis, concluding with a discussion on system integration, calibration, performance assessment, and pathways for future improvements like microcoils and hyperpolarization.

Research done with the help of artificial intelligence, and presented by two AI-generated hosts.