Upgrade of a Bruker NMR Spectrometers Using a Modern Digital Base
С.В. Журенко, A. V. Tkachev, A.V. Gunbin, A.A. Gippius
Abstract
Based on a Bruker MSL-300 nuclear magnetic resonance (NMR) spectrometer, a method has been developed for upgrading the CXP, MSL, and Avance-I series spectrometers by converting them to a modern digital base and replacing analog signal processing with digital processing while preserving the standard radio-frequency (RF) components as much as possible. The upgrade means retaining the 250-W wide-band amplifier, the RF synthesizer with a frequency band of 0–250 MHz, and the narrow-band preamplifier with the complete elimination of an Aspect computer and the standard DISMSL control program. Outdated units for generating RF pulses and registering signals were modified. This enables to significantly improve the maintainability and reliability of the spectrometer and ensure its connection to a modern computer. Comparative measurements of the signal-to-noise ratio for Cu2O samples on 63Cu nuclei revealed a 1.5-fold increase in the sensitivity of the new scheme compared to the original Bruker MSL-300 NMR spectrometer.