ETS-Lindgren HI-2790B Calibration Comparison System - Manual (Page 7)

www.ets-lindgren.com Introduction 7
1.0 Introduction
The ETS-Lindgren HI-2790B Calibration Comparison System is an instrument
calibration comparison system that can be used by microwave oven
manufacturers to comply with the Center for Devices and Radiological Health
(CDRH) requirements as outlined in Guide for Preparing Reports on Radiation
Safety of Microwave Ovens, dated March 1985. The HI-2790B is a complete
system containing all of the equipment necessary to check microwave oven
survey instruments and monitor the calibration stability of these instruments. This
involves checking each instrument periodically to make sure that its response is
within specification, and its calibration remains constant. This must not be
confused with performance of absolute calibration or transfer calibration on the
instrument.
In addition to defining a standard format for data, the information provided in this
manual is intended to guide the oven manufacturer in establishing procedures for
using the HI-2790B system to generate information for reporting to the U.S. Food
and Drug Administration, Department of Health and Human Services, Center for
Devices and Radiological Health.
Note: The HI-2790B system replaces the HI-2790A and HI-2795A
Calibration Comparison Systems. The HI-2790B system offers a
broader, continuous power range from 0.1 to more than 5 mW/cm 2 .
The internal microwave (2.45 GHz) power source offers a more
stable RF signal to the test chamber. The HI-2790B Power/Control
Module has a single mains input operating from 100 to 240 VAC,
50/60 Hz.
General Description
The HI-2790B system consists of:
 A portable anechoic chamber mounted on a frame with castor wheels
for ease of movement.
 A Power/Control Module containing a crystal-controlled 2450 MHz
solid state source and a power meter for monitoring power to the
waveguide and forward, reflected, and transmitted power.