ISSN:
1089-7623
Source:
AIP Digital Archive
Topics:
Physics
,
Electrical Engineering, Measurement and Control Technology
Notes:
Microcoil nuclear magnetic resonance (NMR), using receiver coils of diameters of order 100 μm, is increasingly employed to observe very small (∼0.3 nl) samples with high sensitivity. However, many experimental aspects of microcoil NMR differ greatly from conventional NMR. In particular, the duplexer is a device used to switch between the transmit and receive phases of the experiment. The conventional duplexer is a passive device employing crossed diodes, that switch automatically to transmit mode when high rf power is present. In microcoil NMR, however, the transmitter power is necessarily quite low, with voltages that do not greatly exceed characteristic diode voltage drops. Here we present the complete design and construction methods for a duplexer well suited to the special demands of microcoil NMR. © 2000 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.1150710
