Transients, computer of averaged

Fig. 18. Proton NMR spectrum at 220 Me of human cyanoferrihemoglobin at 36 °C. Different scales were used for the different spectral regions. This spectrum was recorded in a single sweep. The signal-to-noise ratio could be further improved by employing a computer of average transients...

The earliest efforts at combating the signal-to-noise problem involved signal accummulation in a small computer or CATing (Computer of Average Transients). The spectrum was measured, the result stored, and the... 

The high concentrations that are required in most n.m.r. measurements sometimes lead to conclusions incompatible, or only partly compatible, with those derived from other physical techniques, and often traceable to association. One way of overcoming this is to work in a more dilute solution which is scanned several hundreds of times and the cumulated readings plotted after passage through a cat (computer of average transients) to improve the ratio of signal to noise. 

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