Sensitivity improvement of a Varian E-109 EPR spectrometer with a low noise microwave amplifier
- 1 May 1988
- journal article
- research article
- Published by AIP Publishing in Review of Scientific Instruments
- Vol. 59 (5) , 764-766
- https://doi.org/10.1063/1.1139824
Abstract
The installation of a low noise GaAsFET microwave preamplifier into a Varian E‐109 homodyne X‐band EPR spectrometer is described, and measurements of the resulting improvement in sensitivity as a function of microwave power are presented. Particular attention is paid to modification of the automatic frequency control (AFC) system to compensate for the preamplifier gain, which would otherwise result in instability of the AFC servoloop and decreased spectrometer performance at moderate microwave power levels. Specific details are provided for modification of the Varian E‐102 bridge, but the general approach is applicable to other spectrometers.Keywords
This publication has 2 references indexed in Scilit:
- Application of a microwave preamplifier to an ESR spectrometerReview of Scientific Instruments, 1985
- Sensitivity enhancement in ESR/ENDOR spectrometers by use of microwave amplifiersReview of Scientific Instruments, 1978