# A modular, open-source platform for sub-MHz NMR ### Introduction Many students, researchers and hobbyists will be familiar with the [Arduino](https://arduino.cc) open-source-electronics ecosystem, which provides an extraordinarily simple way to interface sensors (or other input devices) and actuators (output) with logic programs, e.g. C code, to create a wide variety of standalone control devices termed embedded systems. A [Nuclear Magnetic Resonance](https://en.wikipedia.org/wiki/Nuclear_magnetic_resonance) (**NMR**) spectrometer can be regarded as one specific type of embedded system: the output is a magnetic field produced by a coil, the input is a magnetic field (detected and recorded by a digitizer), and a pulse programmer keeps timing and data in order. The **NMRduino** is a magnetic resonance spectrometer based on (but we must stress, not endorsed or supported by) Arduino that we have developed over recent years to study hyperpolarized NMR systems, NMR relaxation, high-resolution spectroscopy, and coherent control at low magnetic fields, as well as teach basic principles of magnetic resonance to student beginners Main features are: - Compact, plug-and-play hardware. A credit-card-sized circuit board contains all electronic components and connects to any laptop, desktop or Raspberry Pi computer via USB. Includes pulse programmer and analog sampling up to 100 kHz. - Transparent, intuitive control interface. User-specific pulse sequences (1 μs time resolution) can be written to control both DC and AC magnetic fields up to several hundred kHz. Open access to low-level programming interface for advanced users. - Flexibility. Can be connected to conventional rf-inductive pickup coils, or alternative sensors such as atomic magnetometers. ### Software To get running, you'll need a copy of NMRduino's firmware: [Latest version here](https://github.com/NMRduino/NMRduino/blob/main/Software/MCU/index.md) plus the user interface. Select the version for your operating system: [Raspberry Pi](https://github.com/NMRduino/), [Windows xx](https://github.com/NMRduino/) ### External resources [NMRduino at Open Source Imaging](https://www.opensourceimaging.org/project/nmrduino/), a directory of FOSS/OSHW magnetic resonance projects
[NMRduino in the Journal of Magnetic Resonance](https://doi.org/10.1016/j.jmr.2024.107665). A FREE TO READ article written by the creators of NMRduino, published May 2024