EFFICIENCY ESTIMATION FOR SINGLE-COIL, SEPARATE-INPUT, DOUBLE-TUNED NMR PROBES

The signal-to-noise ratio for the NMR observation of a nucleus using a double-tuned probe depends on the power efficiency of the observe channel. In a similar manner, the minimum decoupling power is a function of the efficiency of the proton channel. Efficiencies are often determined in several steps, which involve measuring electrical characteristics of disassembled probe elements. In this work, we show how efficiencies can be simply computed from measurements of the quality factors of each port, at its resonant frequency. Thus, an index of the probe performance, especially its signal-to-noise ratio, is readily available for the complete, loaded device. © 1991.