An article about magnetic resonance instrumentation in general, but still of interest for researchers that build there own NMR/DNP equipment.
Wheeler, D.D. and M.S. Conradi, Practical exercises for learning to construct NMR/MRI probe circuits. Concepts in Magnetic Resonance Part A, 2012. 40A(1): p. 1-13.
Nine sets of laboratory exercises are designed to acquaint the student with many aspects of NMR/MRI probe resonant circuits. These include demonstrations of stray inductance and capacitance, matching a resonant circuit to 50 Ω, inductive coupling, doubly resonant circuits, loading effects of tissue, and radiation from the probe circuit. Many of the exercises are for the bench, but some are performed in an NMR system. The exercises should lead to an understanding of, as well as some intuitive knowledge about, basic NMR/MRI probe circuits.