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New 915 MHz Low Power Generator for Materials Testing Utilizing an Evanescent Mode Cavity

Published online by Cambridge University Press:  10 February 2011

Charles R. Buffler  and
Per O. Risman
Charles R. Buffler
Affiliation:
Microwave Research Center, 126 Water Street, Marlborough, NH 03455, cbuff@top.monad.net
Per O. Risman
Affiliation:
Microtrans AB, Box 7, S-43821 Landvetter, Sweden, risman@por.se
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Abstract

The economy of utilizing 915 MHz vs. 2450 MHz microwave equipment has long been acknowledged for many industrial processes. A severe roadblock to advancing 915 MHz processing has been the lack of proper equipment to run test trials. At 2450 MHz low power equipment is readily available and inexpensive, even resorting to the use of the consumer microwave ovens. At 915 MHz, however, prototyping systems have only been available using very expensive 5 kW magnetrons. Experimenters have been forced to use 2450 MHz low power equipment to explore scale-up potential for high power 915 MHz systems. Because of wavelength and dielectric property differences, this procedure may give highly erroneous results, sometimes leading to the purchase of production equipment which does not work.

This paper describes an inexpensive, low power, microwave system for prototype testing at 915 MHz. A 600 watt generator is coupled to a specially designed evanescent mode applicator/cavity for the trial testing prior to making a scale-up decision. A description of the generator and evanescent cavity design are presented.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 430: Symposium O – Microwave Processing of Materials V , 1996 , 85
Copyright
Copyright © Materials Research Society 1996

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