Positive-intrinsic-negative diode-based duplexer for microcoil nuclear magnetic resonance

Autor:	D. A. Seeber, J. H. Hoftiezer, Charles H. Pennington
Rok vydání:	2000
Předmět:	Materials science Nuclear magnetic resonance Duplexer Transmitter RF power amplifier Microcoil Instrumentation Sensitivity (electronics) Voltage Diode Power (physics)
Zdroj:	Review of Scientific Instruments. 71:2908-2913
ISSN:	1089-7623 0034-6748
Popis:	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.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::358733202535a61678deb8bd4ee829e3 https://doi.org/10.1063/1.1150710 Zobrazit plný text záznamu