A low–cost Arduino–based NMR console

Time domain nuclear magnetic resonance (TD–NMR) is a non-destructive technique to investigate a samples' physical properties, such as fat and water contents, porosity, viscosity and water states in cell compartments etc., by analysis of the samples' proton relaxations. However, commercial NMR consoles are still expensive, closed–source and unable to be customized for various applications. In this work, we demonstrate a low–cost, easy–to–build and customizable Arduino–based NMR console. The Arduino Due was chosen due to being easy–to–program while delivering high performance. The Arduino conducts four important functions i.e. controlling an RF synthesizer, timing control, data acquisition and PC interface. The NMR console is equipped with a quadrature modulator for RF phase control and a demodulator for signal phase detection. A low–cost HF power amplifier is used to amplify the transmitting signal, while a low noise amplifier TB–411–6+ is combined with an adjustable gain amplifier AD603 to amplify the received signal. The amplified signal is demodulated and collected by the Arduino. The console was successfully used to measure relaxation times of glycerin and mineral oils. The overall cost of the prototype console is approximately 363 USD. The quadrature modulator and demodulator are the key components for future development to be an NMR imaging console. (paper)